Medical apparatus, medical apparatus guide system, capsule type medical apparatus, and capsule type medical apparatus guide apparatus

ABSTRACT

In a capsule  3  as a medical apparatus inserted into a body cavity, the lengthwise direction of the capsule  3  is used as an insert axis, a manipulation/input device  8 , which is magnetized in a direction orthogonal to the insert axis, is disposed at the center position of the insert axis. A magnetic field generation device  4 , which is disposed outside of a body, is caused to generate a vibration magnetic field in a direction parallel with the insert axis of the capsule  3  by turning on a vibration (ON/OFF) switch  8   f  of a manipulation/input device  8  so that couples having lines of action, which are in parallel with the insert axis, are exerted on the capsule  3 , thereby the capsule  3  executes a swiveling motion about the insert axis and smoothly travels along a cavity organ.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a divisional of copending U.S. patentapplication Ser. No. 10/910,738, filed on Aug. 3, 2004 which claims thebenefit of Japanese Patent Applications Nos. 2003-291771 and 2003-288273filed in Japan on Aug. 11, 2003, and Aug. 6, 2003, respectively, thecontents of each of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a medical apparatus inserted into abody cavity, a medical apparatus guide system, which is preferable tothrust and guide the medical apparatus while rotating it, a capsule typemedical apparatus, and a capsule type medical apparatus guide apparatus.

2. Related Art Statement

Conventional arts for thrusting a micro machine in a body to be examinedby a rotation magnetic field are disclosed in Japanese Unexamined PatentApplication Publication Nos. 2001-179700 and 2002-187100. Theseconventional arts disclose a movement control system for a movable micromachine including a magnetic field generation device for generating arotation magnetic field, a robot main body for obtaining a thrust bybeing rotated in response to the rotation magnetic field, a positiondetection device for detecting the position of the robot main body, andmagnetic field change means for changing the direction of the rotationmagnetic field generated by the magnetic field generation unit to directthe robot main body toward a destination where it reaches based on theposition of the robot main body detected by the position detectiondevice.

SUMMARY OF THE INVENTION

A medical apparatus of the present invention includes a couplegeneration device for generating couples having lines of action parallelto an insert axis in a medical apparatus having an insert portioninserted into a body cavity.

A medical apparatus of the present invention includes

a medical apparatus having an insert portion inserted into a body cavityhaving an approximately cylindrical outside shape, a spiral structuredisposed around the side of the medical apparatus main body, a thrustgeneration mechanism having rotation drive means for rotating the spiralstructure about the cylindrical axis of the medical apparatus main bodyand generating a thrust in the direction of the cylindrical axis, andcouple generation means having lines of action in parallel with thecylindrical axis.

A medical apparatus guide system of the present invention for guiding amedical apparatus into a body cavity includes a rotation magnetic field,a magnetic field generation device for generating a magnetic field in adirection perpendicular to the rotation plane of the rotation magneticfield, a medical apparatus main body having an insert portion insertedinto the body cavity, a thrust generation structure disposed to themedical apparatus main body, and a magnet disposed to the medicalapparatus main body with a magnetic pole direction facing a directionsubstantially orthogonal to the thrust generating direction of thethrust generation structure.

A capsule type medical apparatus of the present invention includes acapsule type medical apparatus main body having an insert portioninserted into the body cavity, a thrust generation structure disposed tothe medical apparatus main body, and a magnet disposed to the medicalapparatus main body in the vicinity of the center in the thrustgenerating direction of the capsule medical apparatus main body with amagnetic pole direction facing a direction substantially orthogonal tothe thrust generating direction of the thrust generation structure.

A medical apparatus of the present invention for executing a medicalaction such as an examination, a treatment, or the like in a cavityorgan of a body to be examined is arranged such that a main body iscomposed of a rotation symmetrical member having a symmetrical axis in atraveling direction, at least one of the front portion or the rearportion in a traveling direction of the main body is composed of adiameter-reduced portion having a diameter reduced toward an end and anapproximately hemispherical end shape, an electromagnetic field responseportion is disposed in the main body so that it is acted by the rotationof an electromagnetic field applied from the outside of the body to beexamined, and a spiral structure is disposed on the outside surface ofthe main body and converting the rotating motion generated by theelectromagnetic field response portion into a thrust, wherein an end ofthe spiral structure is disposed to reach the vicinity of an end of themain body.

A medical apparatus guide system of the present invention includes amedical apparatus comprising a main body composed of a rotationsymmetrical member having a symmetrical axis in a traveling direction, adiameter-reduced portion arranged to at least one of the front portionor the rear portion of the main body in a traveling direction and havingan approximately hemispherical end shape whose diameter is reducedtoward an end, an electromagnetic field response portion disposed in themain body and acted by the rotation of an electromagnetic field appliedfrom the outside of the body to be examined, a spiral structure disposedon the outside surface of the main body and converting a rotating motiongenerated by the electromagnetic field response portion into a thrust,wherein an end of the spiral structure is disposed to reach the vicinityof an end of the main body, electromagnetic field generation means forgenerating an electromagnetic field acting on the electromagnetic fieldresponse portion disposed to the medical apparatus, and electromagneticfield control means for controlling the direction of the electromagneticfield generated by the electromagnetic field generation means, whereinthe electromagnetic field generation means generates the electromagneticfield in three-axis directions and rotates the medical apparatus in acavity organ.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic configurational view of a capsule type medicalapparatus guide system having a first embodiment of the presentinvention, the configurational view mainly showing a rotation magneticfield generation device in particular;

FIG. 2 is a block diagram showing the internal arrangements ofrespective portions in the capsule type medical apparatus guide systemhaving the first embodiment of the present invention;

FIG. 3(A) is a side elevational view of a capsule main body;

FIG. 3(B) is a front elevational view of the capsule main body;

FIG. 4(A) is an explanatory view showing the arrangement of amanipulation/input device;

FIG. 4(B) is a view showing an image display screen for displayinginformation corresponding to the manipulation of the manipulation/inputdevice shown in FIG. 4(A);

FIG. 5 is an explanatory view showing how a rotation magnetic fieldchanges, and the like when it is applied;

FIGS. 6(A) and 6(B) are schematic views showing the behavior of couplesreceived by the capsule type medical apparatus when a vibration magneticfield is applied;

FIGS. 7(A) and 7(B) are views showing loci drawn by the extreme end ofthe capsule type medical apparatus when the frequencies and strengths ofthe rotation magnetic field and the vibration magnetic field arechanged;

FIG. 8(A) is a view showing a locus when the frequency of the rotationmagnetic field is set equal to that of the vibration magnetic field, andthe like;

FIG. 8(B) is a view showing a locus drawn by the extreme end of thecapsule type medical apparatus when the frequency of the vibrationmagnetic field is set twice that of the rotation magnetic field;

FIG. 8(C) is a view showing a locus drawn by the extreme end of thecapsule type medical apparatus when a direct current is used in thevibration magnetic field;

FIGS. 9(A), 9(B), and 9(C) are views showing a result of measurement ofa thrust velocity when the rotation magnetic field and the vibrationmagnetic field are applied using a sample;

FIGS. 10(A), 10(B), 10(C), and 10(D) are explanatory views of motions ofthe capsule type medical apparatus when it thrusts in a curved cavityorgan and a wide cavity organ;

FIG. 11 is an explanatory view when the rotation magnetic field and thelike are applied on a coordinate system on which the center axis of thecapsule type medical apparatus is set in an x′-direction;

FIG. 12 is an explanatory view of calculation of the direction of acapsule and the direction of the rotation magnetic field when anindication for changing the direction of the capsule type medicalapparatus is input;

FIG. 13 is an explanatory view showing a new direction of the capsuletype medical apparatus on a polar coordinate system;

FIG. 14 shows a layout of the internal structure of the capsule typemedical apparatus;

FIG. 15 shows a layout of a modification in which a magnet is disposedon the rear end side in FIG. 14;

FIG. 16 shows a layout of a modification in which a magnet is disposedon an observation window side in FIG. 14;

FIG. 17 is an explanatory view of an operation when the vibrationmagnetic field is applied to the layout shown in FIG. 15;

FIGS. 18(A) and 18(B) are explanatory views showing how the motion ofthe capsule is different when it is guided by the magnet disposed in thevicinity of the center of the capsule type medical apparatus main bodyand by the magnet disposed in the vicinity of an end thereof;

FIGS. 19(A) and 19(B) are views showing a capsule type medical apparatusand a pager motor of a second embodiment of the present invention;

FIG. 20 is a sectional view showing a capsule type medical apparatus ofa third embodiment of the present invention;

FIG. 21(A) is a view showing an arrangement of an electromagneticsolenoid device;

FIG. 21(B) shows a capsule type endoscope having a flexible tube at oneside end;

FIG. 22 is a schematic configurational view of a capsule type medicalapparatus guide system having a fourth embodiment of the presentinvention;

FIG. 23 is a block diagram showing a more detailed arrangement of FIG.22;

FIG. 24 is a schematic configurational view showing a schematicarrangement of a magnetic field generation device;

FIG. 25 is a side elevational view showing an external appearance of thecapsule type medical apparatus;

FIG. 26 is a sectional view showing an internal structure of the capsuletype medical apparatus;

FIG. 27 is a side elevational view of a water vessel in which a samplecapsule, which is inserted into a silicon tube, is dipped to measure athrust velocity by applying a rotation magnetic field thereto;

FIG. 28 is a view showing a first sample having a spiral projectiondisposed at an end;

FIGS. 29(A) and 29(B) are graphs showing a result of measurement of thethrust velocity;

FIGS. 30(A) and 30(B) are explanatory views showing an action when thecapsule thrusts in a curved tract;

FIG. 31 is a side elevational view showing a capsule type medicalapparatus of a fifth embodiment of the present invention;

FIG. 32 is a side elevational view showing a capsule type medicalapparatus of a first modification;

FIG. 33 is a side elevational view showing a capsule type medicalapparatus of a second modification;

FIG. 34 is a side elevational view showing a capsule type medicalapparatus of a third modification;

FIG. 35 is a schematic side elevational view showing a pitch of a spiralprojection of a capsule type medical apparatus of a fourth modification;

FIG. 36(A) is an explanatory view showing a capsule type medicalapparatus of a sixth embodiment of the present invention;

FIG. 36(B) is a view showing an image obtained from the capsule typemedical apparatus shown in FIG. 36(A); and

FIG. 37 is a side elevational view, partly in cross section, showing anarrangement of a capsule type medical apparatus of a modification.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Embodiments of the present invention will be explained below withreference to the drawings.

First Embodiment

FIGS. 1 to 18 relate to a first embodiment of the present invention, inwhich FIGS. 1 and 2 show an overall arrangement of a capsule typemedical apparatus guide system of a first embodiment; FIGS. 3(A) and3(B) show a side elevational view and a front elevational view of acapsule main body; FIGS. 4(A) and 4(B) show an image display screenshowing an arrangement of an manipulation/input device and informationcorresponding to the manipulation thereof; FIG. 5 shows how a rotationmagnetic field changes, and the like when it is applied; FIGS. 6(A) and6(B) show the behavior of couples received by the capsule type medicalapparatus when a vibration magnetic field is applied; FIGS. 7(A) and7(B) show views showing loci drawn by the extreme end of the capsuletype medical apparatus when the frequencies and strengths of therotation magnetic field and the vibration magnetic field are changed;FIG. 8(A) is a view showing a locus when the frequency of the rotationmagnetic field is set equal to that of the vibration magnetic field, andthe like; FIG. 8(B) shows a locus drawn by the extreme end of thecapsule type medical apparatus when the frequency of the vibrationmagnetic field is set twice that of the rotation magnetic field; FIG.8(C) is a view showing a locus drawn by the extreme end of the capsuletype medical apparatus when a direct current is used in the vibrationmagnetic field; FIGS. 9(A), 9(B) and 9(C) show a result of measurementand the like of a thrust velocity when the rotation magnetic field andthe vibration magnetic field are applied using a sample; FIGS. 10(A) to10(D) show a motion explanatory views when the capsule type medicalapparatus thrusts in a curved cavity organ and a wide cavity organ; FIG.11 shows an explanatory view when the rotation magnetic field and thelike are applied on a coordinate system on which the center axis of thecapsule type medical apparatus is set in an x′-direction; FIG. 12 is anexplanatory view of calculation of the direction of a capsule and thedirection of the rotation magnetic field when an indication for changingthe direction of the capsule type medical apparatus is input; FIG. 13shows an explanatory view showing a new direction of the capsule typemedical apparatus on an absolute coordinate system; FIG. 14 shows alayout of an internal structure of the capsule type medical apparatus;FIG. 15 shows a layout of a modification in which a magnet is disposedon the rear end side in FIG. 14; FIG. 16 shows a layout of amodification in which a magnet is disposed on an observation window sidein FIG. 14; FIG. 17 shows an explanatory view of an operation when thevibration magnetic field is applied to the layout shown in FIG. 15; andFIGS. 18(A) and 18(B) show explanatory views showing how the motion ofthe capsule is different when it is guided by the magnet disposed in thevicinity of the center of the capsule type medical apparatus main bodyand by the magnet disposed in the vicinity of an end thereof.

As shown in FIGS. 1 and 2, a capsule type medical apparatus guide system1 of the first embodiment of the medical apparatus guide system of thepresent invention includes a capsule type medical apparatus 3(hereinafter, abbreviated to as capsule), a magnetic field generationdevice 4, a magnetic field controller (or power supply controller) 5, aprocessing device 6 composed of a personal computer or the like, adisplay device 7, and a manipulation/input device 8. The capsule 3 isinserted (guided) into a body cavity of a not shown patient and acts asa capsule type endoscope for picking up the image of the inside of thebody cavity; the magnetic field generation device 4 is disposed aroundthe patient, that is, externally of the patient' body and applies arotation magnetic field and a couple generating magnetic field (orvibration magnetic field) to the capsule 3; the magnetic fieldcontroller 5 controls the supply of a drive current which generates therotation magnetic field and the couple generating magnetic field (orvibration magnetic field) to the magnetic field generation device 4; theprocessing device 6 is disposed externally of the patient' body, andexecutes image processing through a wireless communication with thecapsule 3 as well as controls the direction, magnitude, and the like ofthe rotation magnetic field and the couple generating magnetic field (orvibration magnetic field) applied to the capsule 3 by controlling themagnetic field controller 5 according to a manipulation executed by amanipulator; the display device 7 is connected to the processing device6 and displays an image and the like recorded by the capsule 3; and themanipulation/input device 8 is connected to the processing device 6 andmanipulated by the manipulator such an operator and the like, and anindication signal corresponding to the manipulation is indicated andinput through the manipulation/input device 8.

As shown in FIG. 4(A), the manipulation/input device 8 includes adirection input unit 8 a through which a direction, in which the capsule3 inserted into the body is intended to thrust, is input and indicated,a rotation frequency input unit 8 b, a rotation magnetic field strengthadjustment unit 8 c, a vibration (couple generating) magnetic fieldstrength adjustment unit 8 d, a vibration (couple generating) magneticfield frequency adjustment unit 8 e, and a vibration (or couplegenerating) ON/OFF switch (abbreviated as vibration switch) 8 f. Therotation frequency input unit 8 b generates a signal for indicating arotation magnetic field having a rotation frequency corresponding to amanipulation; the rotation magnetic field strength adjustment unit 8 cadjusts the strength of the rotation magnetic field; and the vibrationswitch 8 f is disposed at, for example, an apex of a joy stick 9 thatconstitutes the direction input unit 8 a and turns on and off theapplication of the vibration (or couple generating) magnetic field. Notethat, in the following description, the vibration (or couple generating)magnetic field is described as a vibration magnetic field (in almost allthe cases).

As shown in FIG. 3, the capsule 3 is formed in an approximatelycylindrical shape or a capsule shape and composed of an exterior vessel11 which also acts as an insert portion inserted into a body. Theexterior vessel 11 has a spiral projection (or screw portion) 12 formedaround the outer circumferential surface thereof, the spiral projection12 acting as a thrust generating structural portion for converting arotation into a thrust (thrust force).

The spiral projection 12 has a round sectional structure having anapproximately hemispherical shape and the like and disposed around theouter circumferential surface of the exterior vessel 11 so that it is insmooth contact with the inside wall surface of the body.

Further, the capsule 3 accommodates an image pickup means in the insidethereof hermetically sealed by the exterior vessel 11, the image pickupmeans being composed of an objective lens 13 and an image pickup element14 disposed at a focusing position of the objective lens 13. Further,the exterior vessel 11 accommodates therein a magnet (permanent magnet)16, in addition to illumination elements 15 (refer to FIG. 2), which arenecessary to execute picking up an image, and the like, the magnet 16being used to more smoothly thrust the capsule 3.

As shown in FIGS. 3(A) and 3(B), the objective lens 13 is disposedinwardly of, for example, a hemispherical transparent extreme end cover11 a in the exterior vessel 11 with its optical axis in agreement with acenter axis C which is said to act as an insert axis of the cylindricalcapsule 3. As shown in FIG. 3(B), an observation window 17 is formed ata central portion of the extreme end cover 11 a. Note that, although notshown in FIGS. 3(A) and 3(B), the illumination elements 15 are disposedaround the objective lens 13.

Accordingly, in this case, the direction of the filed of view of theobjective lens 13 is in agreement with the optical axis direction of theobjective lens 13, that is, in agreement with a direction along thecylindrical center axis C of the capsule 3.

Further, as shown in FIGS. 3(A) and 3(B), the magnet 16, which isdisposed in the vicinity of the center of the capsule 3 in a lengthwisedirection, is disposed such that an N-pole and an S-pole are disposed ina direction orthogonal to the center axis C. In this case, the magnet 16is disposed with its center in agreement with the position of the centerof gravity of the capsule 3. Accordingly, when a magnetic field isapplied from the outside, the center of a magnetic force acting on themagnet 16 agrees with the position of the center of gravity of thecapsule 3 so that the capsule 3 can be smoothly thrust magnetically.

Further, as shown in FIG. 3(B), the magnet 16 is disposed such that themagnetized direction thereof, that is, the direction of an electricdipole agrees with the specific direction in which the image pickupelement 14 is disposed.

That is, an up-direction when an image recorded by the image pickupelement 14 is displayed is set in a direction from the S-pole to theN-pole of the magnet.

Then, the magnet 16 is magnetically rotated by applying the rotationmagnetic field to the capsule 3 by the magnetic field generation device4 to thereby rotate the capsule 3 having the magnet 16 fixed thereintogether with the magnet 16. At the time, the spiral projection 12formed on the outer circumferential surface of the capsule 3 is rotatedin contact with the inner wall of the body cavity so that the capsule 3can be thrust.

Further, FIGS. 6(A) and 6(B) schematically show a fundamental function(action) of the embodiment. As shown in the figures, the magnetic fieldgeneration device 4 can apply a vibration magnetic field (couplegenerating magnetic field) Hm whose magnetic field direction changes inthe center axis C direction of the capsule 3 thereto (by turning on thevibration switch 8 f). It is a feature of the invention that forces,which are parallel to the center axis C as shown by arrows in FIGS. 6(A)and 6(B) and have the same magnitude in an opposite direction (that is,couples) can be exerted on the magnet 16 built in the capsule 3.

In this case, the couples are parallel with the center axis C atrespective points of both the magnetic poles of the magnet 16 on a lineconnecting them, have the same magnitude of forces in an oppositedirection, and are exerted so as to rotate the capsule 3.

In the embodiment, the couples are exerted to the magnet 16 by themagnetic field applied from the outside. However, as explained in asecond embodiment and the like to be described below, the capsule 3 mayhave such a structure that an inclining (swinging) mechanism causes thedirection of the lengthwise insert axis of the capsule 3 to makevibration, inclination or the like so that the capsule 3 swivels andthat pseud-couple generating means changes the position of a center ofgravity (so that a force which corresponds one of couples is generatedor exerted).

Further, in the embodiment, when the capsule having the magnet 16 builttherein is controlled by an external magnetic field, the direction, towhich the upper direction of the image recorded by the capsule 3 faces,can be found from the direction of the external magnetic field.

As shown in FIG. 2, accommodated in the capsule 3 are a signalprocessing circuit 20, a memory 21, a wireless circuit 22, a capsulecontrol circuit 23, and batteries 24, in addition to the objective lens13, the image pickup element 14, the illumination elements 15, and themagnet 16 which are described above. The signal processing circuit 20subjects a signal recorded by the image pickup element 14 to signalprocessing; the memory 21 temporarily stores a digital video signalcreated by the signal processing circuit 20; the wireless circuit 22modulates the video signal read out from the memory 21 with a highfrequency signal and converts it into a signal which is transmitted bywireless, modulates the control signal transmitted from the processingdevice 6, and so on; the capsule control circuit 23 controls the capsule3 such as the signal processing circuit 20 and the like; and thebatteries 24 supply an operation power to electric systems in thecapsule 3 such as the signal processing circuit 20 and the like.

Further, the processing device 6, which makes a wireless communicationwith the capsule 3, includes a wireless circuit 25, a data processingcircuit 26, a control circuit 27, and a memory circuit 28. The wirelesscircuit 25 makes a wireless communication with the wireless circuit 22,the data processing circuit 26 is connected to the wireless circuit 25and subjects the image data sent from the capsule 3 to data processingsuch as image display processing and the like; the control circuit 27controls the data processing circuit 26, the power supply controller 5and the like; and the memory circuit 28 stores the information of thestate of the rotation magnetic field generated by the magnetic fieldgeneration device 4 through the power supply controller 5 and theinformation set by the direction input unit 8 a and the like.

The display device 7 is connected to the data processing circuit 26, andthe image, which is recorded by the image pickup element 14 andprocessed by the data processing circuit 26 through the wirelesscircuits 22 and 25, and the like are displayed thereon. Further, sinceimages are recorded by the capsule 3 while it is being rotated, the dataprocessing circuit 26 executes image processing for correcting thedirections of the images to be displayed on the display device 7 to apredetermined direction so that the operator can observe the imageseasily (described in Japanese Patent Application No. 2002-105493).

Indication signals corresponding to a manipulation are input to thecontrol circuit 27 from the direction input unit 8 a, the rotationfrequency input unit 8 b, and the like which constitute themanipulation/input device 8, and the control circuit 27 executes acontrol operation corresponding to the indication signals.

Further, the control circuit 27 is connected to the memory circuit 28 sothat the memory circuit 28 stores the information of direction of therotation magnetic field and the information of direction of the magneticfield at all times, these rotation magnetic field and the magnetic fieldbeing generated by the magnetic field generation device 4 through themagnetic field controller 5. Then, when a manipulation for changing thedirection of the rotation magnetic field and the direction of themagnetic field is executed thereafter, the control circuit 27 cancontinuously change the direction of the rotation magnetic field and thedirection of the magnetic field so that they can be smoothly changed.Note that the memory circuit 28 may be disposed in the inside of thecontrol circuit 27.

Further, the magnetic field controller 5 connected to the controlcircuit 27 includes an alternate current generator/controller 31 and adriver portion 32. The alternate current generator/controller 31 iscomposed of three alternate current generation/control circuits forgenerating alternate currents as well as controlling the frequencies andphases of the alternate currents; and the driver portion 32 is composedof three drivers for amplifying the respective alternate currents,respectively. The currents output from the three drivers are supplied tothree electromagnets 33 a, 33 b, 33 c that constitute the magnetic fieldgeneration device 4, respectively.

In this case, the electromagnets 33 a, 33 b, 33 c are disposed such thatthey generate magnetic fields in the three-axis directions that areorthogonal to each other. Contemplated as an example of the magneticfield generation device 4 is a three-axis Helmholtz coil in which therespective electromagnets 33 a are composed Helmholtz coils and thedirections of the magnetic fields generated thereby are orthogonal toeach other.

Then, a signal for indicating a magnetic field direction can begenerated by manipulating the direction input unit 8 a constituting themanipulation/input device 8 shown in FIG. 4(A). A signal for indicatinga rotation magnetic field having a rotation frequency corresponding amanipulation can be generated by manipulating the rotation frequencyinput unit 8 b. The (alternate current or periodic) vibration magneticfield, which are set by the vibration magnetic field strength adjustmentunit 8 d and the like, can be generated by manipulating the vibrationswitch 8 f. Accordingly, there can be generated couples which rotate thelengthwise center axis C itself of the capsule 3 about the center pointthereof with respect to the magnet 16 of the capsule 3. In this case,since an alternate current is periodically applied to change thedirection of the vibration magnetic field (exerted as couples) to aninverse direction before the center axis C itself is perfectly rotated,the capsule 3 is inclined or vibrated.

Note that, in FIG. 4(A), when the joy stick 9 in the direction inputunit 8 a is inclined in a direction in which the capsule 3 is desired tomove, a rotation magnetic field, which moves the capsule 3 in thedesired direction, is generated.

FIG. 5 shows the behavior of the capsule 3 when, for example, therotation magnetic field is applied. The magnet 16 built in the capsule 3can be rotated by applying the rotation magnetic field to the capsule 3,and the capsule 3 can be moved forward and backward by the rotation ofthe magnet 16.

Then, as shown in FIG. 5, a rotation magnetic field is applied to thecapsule 3 such that a pole whose direction changes on the plane of therotation magnetic field perpendicular to the direction (y′ in FIG. 5) ofthe lengthwise center axis C of the capsule 3. The capsule 3 is rotatedabout the lengthwise direction thereof together with the magnet 16 fixedin the capsule 3 in a direction perpendicular to the lengthwisedirection. Therefore, the capsule 3 can be engaged with the inside wallof the body cavity through the spiral projection 12 shown in FIG. 3according to the rotational direction of the magnet 16 and moved forwardor backward.

Further, in the embodiment, a vibration magnetic field (couplegenerating magnetic field) can be applied to the capsule 3, thevibration magnetic field acting to swing (vibrate) the magnet 16 aboutthe direction y′ of the lengthwise center axis C in FIG. 5. When thevibration magnetic field is applied, the lengthwise direction can bechanged (vibrated) from the state shown by a solid line to the stateshown by, for example, a dotted line (the direction of the center axisis shown by yz′).

With the above operation, the capsule 3 is rotated about the lengthwisecenter axis C as well as decentered so that the direction of the centeraxis C of rotation of the capsule 3 inclines. That is, the capsule 3 canbe placed in a state as if the rotation torque of a rotating top isreduced and the axle of the top is swung by the action of gravity(hereinafter, this motion will be called a zigzag motion).

With the above motion, when the capsule 3 is moved forward or backwardin a body cavity having approximately the same diameter as that of thecapsule 3 along the lengthwise direction of the body cavity, the capsule3 can be smoothly moved by applying a rotation magnetic field whichrotates the capsule 3 about the lengthwise direction thereof.

In contrast, when the capsule 3 is simply rotated about the lengthwisedirection and comes into contact with a curved portion of a body cavity(refer to FIG. 10(A)), the capsule 3 may not be smoothly moved in acurved direction.

In this case, the capsule 3 is caused to execute the zigzag motion byapplying a vibration magnetic field thereto so that a force is exertedon the capsule 3 to rotate the lengthwise center axis C of the capsule 3along the axis about the center thereof as described above. With thisoperation, when the lengthwise direction is in agreement with the curveddirection of the body cavity while the zigzag motion is being executed,the capsule 3 can be smoothly moved in the curved direction (which willbe described later with reference to FIG. 10(A)).

Note that the state of the capsule 3 or the state of the rotationmagnetic field are always grasped so that the direction of the rotationmagnetic field can be controlled in any arbitrary desired direction froma present traveling direction by inclining the joy stick 9. In theembodiment, the state of the rotation magnetic field (specifically, thedirection of the rotation magnetic field and the direction of a magneticfield) is stored in the memory circuit 28 at all times.

Specifically, the indication signal of the manipulation in themanipulation/input device 8 shown in FIG. 2 is input to the controlcircuit 27. The control circuit 27 outputs a control signal forgenerating a rotation magnetic field corresponding to the indicationsignal to the magnetic field controller 5 as well as stores theinformation of the direction of the rotation magnetic field and thedirection of the magnetic field in the memory circuit 28.

Accordingly, the memory circuit 28 always stores the information of thedirection of the rotation magnetic field generated by the magnetic fieldgeneration device 4 and the information of the direction of the magneticfield that changes periodically to form the rotation magnetic field.

Note that the memory circuit 28 is not limited to the case that itstores the information corresponding to the control signal of thedirection of the rotation magnetic field and the direction of themagnetic field from the control circuit 27. That is, the information fordetermining the directions of the rotation magnetic field and themagnetic field, which are actually output to the magnetic fieldgeneration device 4 through the alternate current generator/controller31 and the driver portion 32 in the magnetic field controller 5 inresponse to the control signal output from the control circuit 27 to themagnetic field controller 5, may be sent to the control circuit 27 fromthe magnetic field controller 5 side and stored in the memory circuit28.

Further, in the embodiment, when the application of the rotationmagnetic field begins and stops, and when the direction and the like ofthe rotation magnetic field (in other words, the traveling direction ofthe capsule) are changed, the rotation magnetic field is controlled tocontinuously change so that a force is not abruptly exerted but smoothlyexerted on the capsule 3.

Further, in the embodiment, the images recorded by the image pickupelement 14 are also rotated by the rotation of the capsule 3. When theimages are displayed on the display device 7 as they are, the rotatingimages are also displayed, which deteriorates the manipulating propertyof the direction input unit 8 a for indicating a desired direction andmakes a manipulation to the desired direction. Thus, it is desired tostop the rotation of the displayed images.

Accordingly, in the embodiment, the data processing circuit 26 and thecontrol circuit 27 execute processing for correcting the rotating imagesto images whose rotation is stopped as explained in Japanese PatentApplication No. 2002-105493.

Note that an image may displayed by rotating it based on the informationof a magnetic field direction so that the rotation of the capsule 3 iscanceled (otherwise, a still image may be displayed in a predetermineddirection by executing image correlation processing and the like).

Then, as shown in FIG. 4(B), a still image recorded by the image pickupelement 14 is displayed in, for example, a circular display area 7 b ina display screen 7 a of the display device 7 as well as a manipulatingdirection of the joy stick 9 is shown by an arrow 7 c, and an amount ofmanipulation of the joy stick 9 is shown by the size of the arrow 7 c.Further, forward traveling/backward traveling is shown by a color of thearrow 7 c.

Further, a frequency of the rotation magnetic field is displayed in arotation magnetic field frequency display area 7 d at, for example, alower corner of the display screen 7 a.

First, typical actions of the rotation magnetic field and the vibrationmagnetic field, which are features of the embodiment arranged asdescribed above, will be explained.

FIGS. 6(A) and 6(B) show a state that a vibration magnetic field Hm isapplied. In FIG. 6(A), the vibration magnetic field Hm causes couples tobe exerted as shown by a line of action shown by an arrow, the couplesrotating the magnet 16 fixed in the capsule 3 counterclockwise. Thecouples are exerted in a direction parallel to the center axis C of thecapsule 3.

The capsule 3 receives forces (couples) from the vibration magneticfield Hm, the couples rotating the capsule 3 in the direction shown by atwo-dot-and-dash line from the state shown by a solid line.

Further, when a vibration magnetic field Hm having a direction oppositeto that shown in FIG. 6(A) is generated, couples, which rotate themagnet 16 fixed in the inside of the capsule 3 clockwise, are exerted onthe capsule 3 as shown by FIG. 6(B), thereby the capsule 3 is rotated inthe direction shown by a two-dot-and-dash line from the state shown by asolid line.

Further, FIG. 7(A) shows a locus Tr of the capsule 3 when it is viewedfrom the extreme end surface side thereof in the state that a rotationmagnetic field Hr and the vibration magnetic field Hm are applied,wherein the relation between the frequency fr of the rotation magneticfield Hr and the frequency fm of the vibration magnetic field Hm is setto fr<fm.

Further, FIG. 7(B) shows the locus Tr of the capsule 3 in the state thatthe strength of the vibration magnetic field Hm is set one half that ofthe rotation magnetic field Hr in FIG. 7(A). In FIG. 7(B), the angle, atwhich the capsule 3 swivels from the center of rotation, is reduced toone half that in FIG. 7(A).

Further, FIG. 8(A) shows the locus Tr of the capsule 3 when thefrequency fr of the rotation magnetic field Hr is set equal to thefrequency fm of the vibration magnetic field Hm, that is, fr=fm in FIG.7(A).

Under the above condition, the capsule 3 is placed in such a movingstate (locus Tr) that it swivels while decentering on one side (leftside in FIG. 8(A)).

Accordingly, this is effective when it is desired to push and widen abody cavity to one side.

Further, FIG. 8(B) shows the locus Tr of the capsule 3 when thefrequency fr of the rotation magnetic field Hr is set one half thefrequency fm of the vibration magnetic field Hm, that is, fr=fm/2 inFIG. 7(A).

Further, the case that the vibration magnetic field Hm is periodicallychanged has been described above. However, in the case in which thevibration magnetic field Hm may be applied as a magnetic field that doesnot change (fm=0, Hm ≠0), the locus Tr of the capsule 3 turns in thesame frequency as that of the frequency fr of the rotation magneticfield Hr as shown in FIG. 8(C).

Further, as shown in FIG. 9(A), this embodiment creates a statesimulating that the capsule 3 is inserted into the tube of a body cavityby filling a vessel 31 with water 32, and placing a silicon tube 33,into which the capsule 3 is inserted, on the bottom of the vessel 31.

Then, the vessel 31 is disposed in the magnetic field generation device4 shown in FIG. 1, and a rotation magnetic field, which caused thesilicon tube 33 to travel right (forward) and left (backward) in thelengthwise direction (right and left direction in FIG. 9(A)) of thesilicon tube 33, is applied as well as a vibration magnetic field isapplied after its frequency is changed. Then, a period of time duringwhich the capsule 3 moved 2 cm is measured, and a moving velocity of thecapsule 3 during the time is calculated.

In this case, the frequency of the rotation magnetic field is set to 1Hz, the strength of the rotation magnetic field is set to 100 Oe, thestrength of the vibration magnetic field is set to 50 Oe, a water levelis set to 20 cm, and two spiral projections 12, which are formed on thecapsule 3 at a forming angle of 45°, are employed. Further, in thisembodiment, the moving velocity is calculated in the state that thesilicon tube 33 is slightly inclined downward in a right direction (thatis, the left side of the tube is raised). That is, forward traveling(descending) is executed in the right direction, and backward traveling(ascending) is executed in the left direction.

A result of measurement in the backward traveling is as shown in FIG.9(B), and a result of measurement in the forward traveling is as shownin FIG. 9(C). From the results shown in FIGS. 9(B) and 9(C), it iseffective to cause the capsule 3 to travel, in particular, backward inthe ascending direction to make the frequency of the vibration magneticfield higher than that of the rotation magnetic field.

Further, under the condition of this embodiment, data shows that it iseffective to a thrust velocity to set the frequency of the vibrationmagnetic field to about 2 to 10 Hz. Further, the data shows that it iseffective to the thrust velocity to set the frequency of the vibrationmagnetic field to about 2 to 10 times that of the rotation magneticfield.

Next, an overall action of the embodiment will be explained.

When the inside of a body cavity is examined with the capsule 3, apatient swallows the capsule 3. When the capsule 3 inserted into thebody cavity passes through an esophagus and the like, an image recordedby the image pickup element 14 while being illuminated with theillumination elements 15 is transmitted by wireless to the processingdevice 6 outside of a body through the wireless circuit 22.

The processing device 6 stores image data, which is received by thewireless circuit 25 and demodulated, in an image storing device (such asa hard disc or the like) disposed in the data processing circuit 26 andthe like as well as subjects the image data to display processing andoutputs it to the display device 7, thereby the images sequentiallyrecorded by the capsule 3 are displayed thereon.

The operator can assume an approximate present position of the capsule 3in the body cavity from the images displayed on the display device 7.When the operator determines that the esophagus, for example, is beingrecorded regardless of that a portion to be examined is, for example, aportion located on a deeper side such as an intestinum tenue and thelike, it is preferable to move the capsule 3 more speedily throughportions on the way. In this case, the direction (direction of a normalline) of the rotation magnetic field generated by the magnetic fieldgeneration device 4 is initially set on a lower side of the patientalong his or her body height. Note that, the spiral projection 12provided with the capsule 3 in this case is formed in, for example, aright screw state assuming that the direction of a field of view throughwhich an image is recorded by the image pickup element 14 is a directionfacing a front side.

When, for example, the direction input unit 8 a and the like areinitially manipulated to generate the rotation magnetic field, thecontrol circuit 27 starts a setting circuit 29 and displays an initialstate setting screen on the display device 7 or the like so that theoperator can select the direction of the rotation magnetic fieldgenerated in the initially set state. This is because that informationcorresponding to the state of the rotation magnetic field just beforethe initial manipulation of the direction input unit 8 a and the like isnot stored in the memory circuit 28. Then, the operator indicates toinitially generate the rotation magnetic field in the direction on thelower side of the patient along his or her body height, thereby theinitial generation information of the rotation magnetic field is storedin the memory circuit 28.

Further, it is also possible to set the magnitude (amplitude) of therotation magnetic field by the setting circuit 29 so that a rotationmagnetic field having a value exceeding the magnitude is not generated.The information set by the setting circuit 29 is stored in the memorycircuit 28.

Then, the control circuit 27 reads out the information stored in thememory circuit 28 and controls the information to generate the rotationmagnetic field such that the direction thereof is set on the lower sideof the patient along his or her body height by inclining the joy stick 9and the manipulation lever 8 b of the manipulation/input device 8 shownin FIG. 4(A). That is, the rotation magnetic field is generated by themagnetic field generation device 4 through the magnetic field controller5 based on the information read out from the memory circuit 28.

As described above, the rotation magnetic field is applied from theoutside of the body, and a magnetic torque is exerted on the magnet 16built in the capsule 3 inserted into the body cavity, and the capsule 3is rotated. At the time, the capsule 3 is rotated as if a screw isrotated with the spiral projection 12 formed on the outercircumferential surface of the capsule 3 in contact with the inside wallof the body cavity, thereby the capsule 3 is thrust promptly.

Further, the information of the state of the rotation magnetic field(the direction of the rotation magnetic field and the direction of themagnetic field) is stored in the memory circuit 28 at all times, and theinformation of the state of the rotation magnetic field in the statethat the application thereof is stopped is also stored in the memorycircuit 28.

Then, when a manipulation for applying the rotation magnetic field isexecuted again, a rotation magnetic field similar to the case that therotation magnetic field is stopped is generated based on the informationstored in the memory circuit 28.

The capsule 3 can be thrust along the tract in the body cavity asdescribed above. When, however, when a narrower curved portion 42 existsin a relatively narrow cavity 41 and is curved as shown in, for example,FIG. 10(A), it may be difficult to cause the capsule 3 to effectivelytravel along the curved portion 42 only by the rotation magnetic field.

In this case, the capsule 3 can be caused to make the zigzag motionwhile swiveling about the axis along the lengthwise direction thereof byapplying a vibration magnetic field together with the rotation magneticfield as shown in FIG. 7(A) and the like so as to further exert coupleson the capsule 3.

The cavity portion of the curved portion 42 is pressed and widened bythe above swivel action as shown by a dotted line of FIG. 10(A) as wellas the capsule 3 can be thrust in the curving direction of the curvedportion 42 when it faces the curving direction.

Further, FIG. 10(B) shows an action when the capsule 3 is effectivelythrust through a cavity 41 larger than the outside diameter of thecapsule 3.

As shown in FIG. 10(B), when it is intended to thrust the capsule 3through the cavity 41 larger than the outside diameter of the capsule 3,the simple application of the rotation magnetic field is liable torotate the capsule 3 at idle, and thus the capsule 3 is liable to travelat a slow velocity. This is because (the spiral projection 12 formedaround) the outer circumferential surface of the capsule 3 is engagedwith the inside surface of the cavity 41 (portion to be caught) in asmall portion as shown in FIG. 10(C) or 10(D).

Note that FIG. 10(D) shows the state of the capsule 3 when it is viewedin the direction of an arrow A in FIG. 10(C), and when the capsule 3 issimply rotated, the capsule 3 rotates with position thereof lesschanged, and a function of running idle is lowered.

In this case, the capsule 3 is caused to execute a swiveling motion asshown in FIG. 10(B) by applying the vibration magnetic field togetherwith the rotation magnetic field as shown in FIG. 7(A) and the like sothat the effective outside diameter of the capsule 3 is increased in thestate of the swiveling motion as well as a traveling direction isperiodically changed, thereby the capsule 3 can be effectively thrusteven in the case of the wide cavity 41 by increasing the engagingportion of the capsule 3 with the inside wall of the cavity 41.

Further, it is possible to thrust the capsule 3 stably and effectivelythrough the cavity 41 having an inside diameter larger than the outsidediameter of the capsule 3 by causing the capsule 3 to execute theswiveling motion (zigzag motion) as shown in FIG. 10(B) as well as it isalso possible to image the inside wall of the cavity 41 in a largerrange by substantially increasing an imaging area by executing thezigzag motion.

Further, as described above, in the embodiment, the manipulatingdirection and the like of the joy stick 9 are shown by the arrow 7 c asshown in FIG. 4(B) so that the traveling direction of the capsule 3 canbe indicted in a recorded image. Then, the magnetic field generationdevice 4 generates a rotation magnetic field is generated so that thecapsule 3 can travel in the indicated direction according to thedirection.

The control circuit 27 executes processing for calculating the directionin which the rotation magnetic field is generated in this case, and themagnetic field generation device 4 generates the rotation magnetic fieldcorresponding to the indicated direction through the magnetic fieldcontrol circuit 5.

An operation for generating the rotation magnetic field in this casewill be explained below in detail.

Here, a rotation magnetic field strength, a vibration magnetic fieldstrength and the like, which depend on an input time t, are shown byHr(t), Hm(t) and the like.

-   rotation magnetic field strength: Hr(t)→set by 8 c-   vibration magnetic field strength: Hm(t)→set by 8 d-   frequency of rotation magnetic field: fr(t)→set by 8 b-   frequency of vibration magnetic field: fm(t)→set by 8 e-   sampling cycle: Ts→time intervals at which the system switches a    magnetic field strength or at which the input amounts of the    joystick and the like are read-   phase of present rotation: β(t)-   phase of present couples: α(t)-   parameter for determining an amount of change of direction: C-   Vy′(t): input amount in y′ direction of joystick 8 a at time t-   Vz′(t): input amount in z′ direction of joystick 8 a at time t

FIG. 11 shows a coordinate system (x′, y′, z′) on which the center axisdirection of the capsule 3 is set to x′. In this coordinate system (x′,y′, z′), since the center axis direction of the capsule 3 is set to x′,the capsule 3 is caused to travel in the direction of the center axisx′thereof, and the magnetic field is set as described below in the statethe vibration magnetic field is applied in the direction of the centeraxis x′.Hx′(t+Ts)=Hm(t)cos(α(t)+2πTsfm(t))Hy′(t+Ts)=Hr(t)cos(β(t)+2πTsfr(t))Hz′(t+Ts)=Hr(t)sin(β(t)+2πTsfr(t))Hy′, Hz′ show the rotation magnetic fields, and Hx′ corresponds to thevibration magnetic field.

Here, the present phases within a trigonometric function are shown asfollows and used below.α(t+Ts)=α(t)+2πTsfm(t)β(t+Ts)=β(t)+2πTsfr(t)

FIG. 12 shows an explanatory view of a calculation of a new direction ofthe capsule 3 when an indication of direction of the capsule 3 is input.

It is assumed in the state shown in FIG. 12 that a capsule direction (adirection covered by an angle between an y′-axis and an angle γ) isindicated to the capsule 3 (whose center axis direction is x′) to changethe traveling direction thereof as shown by an arrow.

In this case, when the coordinate system is rotated about a rotationcenter axis p perpendicular to the indicated capsule direction, thedirection of a new x′ axis is the direction of the rotation magneticfield.

The calculation of the rotation is realized by the following processes.

-   (1) rotation of −γ about x′ axis (arrow (1) in FIG. 12)-   (2) rotation of δ about z′ axis (arrow (2) in FIG. 12)-   (3) rotation of γ about x′ axis (arrow (3) in FIG. 12)

Here, δ shows the input amounts Vy′(t), Vz′(t) of the joy stick 9.V(t)=((Vy′(t)²+(Vz′(t)²)^(1/2)δ(t)=C×V(t)γ=sin⁻¹(Vz′(t)/V(t))

Accordingly, a transformation matrix in which δ(t) rotation is executedabout the rotation center axis p is shown as follows using a rotationmatrix R_(γ) ^(x′), R_(δ(t)) ^(z′), R_(−γ) ^(x′) corresponding to themanipulations (1), (2), (3).R _(δ(t)) ^(p) =R _(γ) ^(x′) R _(δ(t)) ^(z′) R _(−γ) ^(x′)

Here, Expressions 1 are shown as follows, and they are rotation matrixesabout respective axes.

$\begin{matrix}\begin{matrix}\begin{matrix}{R_{\gamma{(t)}}^{x^{\prime}} = \begin{pmatrix}1 & 0 & 0 \\0 & {\cos\;\gamma} & {{- \sin}\;\gamma} \\0 & {\sin\;\gamma} & {\cos\;\gamma}\end{pmatrix}} \\{R_{\delta{(t)}}^{z^{\prime}} = \begin{pmatrix}{\cos\;{\delta(t)}} & {{- \sin}\;{\delta(t)}} & 0 \\{\sin\;{\delta(t)}} & {\cos\;{\delta(t)}} & 0 \\0 & 0 & 1\end{pmatrix}}\end{matrix} \\{R_{- {\gamma{(t)}}}^{x^{\prime}} = \begin{pmatrix}1 & 0 & 0 \\0 & {\cos\;\gamma} & {\sin\;\gamma} \\0 & {{- \sin}\;\gamma} & {\cos\;\gamma}\end{pmatrix}}\end{matrix} & \left( {{Expressions}\mspace{14mu} 1} \right)\end{matrix}$

Accordingly, a magnetic field to be applied anew is shown by Expression2 using these rotation matrixes.

$\begin{matrix}{\begin{pmatrix}{{Hx}^{\prime}\left( {t + {Ts}} \right)} \\{{Hy}^{\prime}\left( {t + {Ts}} \right)} \\{H\;{z^{\prime}\left( {t + {Ts}} \right)}}\end{pmatrix} = {R_{\gamma{(t)}}^{x^{\prime}}R_{\delta{(t)}}^{z^{\prime}}{R_{- {\gamma{(t)}}}^{x^{\prime}}\begin{pmatrix}{{{{Hx}^{\prime}\left( {t + {Ts}} \right)}❘{v(t)}} = 0} \\{{{{Hy}^{\prime}\left( {t + {Ts}} \right)}❘{v(t)}} = 0} \\{{{H\;{z^{\prime}\left( {t + {Ts}} \right)}}❘{v(t)}} = 0}\end{pmatrix}}}} & \left( {{Expression}\mspace{14mu} 2} \right)\end{matrix}$However, Hx′(t+Ts)|_(v(t)=0), Hy′(t+Ts)|_(v(t)=0), Hz′(t+Ts)|_(v(t)=0)shows the respective magnetic fields in x′, y′, Z′ directions in t+Tswhen V(t)=0.

In contrast, the magnetic fields generated by the three-axis Helmholtzcoil at the time t are shown by (Hx(t) Hy(t) Hz(t)).

Further, when the direction of the capsule 3 is shown using φ(t), θ(t),it is as shown in FIG. 13. Further, when the magnetic field side istransformed from a coordinate system x′, y′, z′ to the coordinate systemx, y, z, it is shown by Expressions 3 at the time t+Ts.

$\begin{matrix}{\begin{pmatrix}{{Hx}\left( {t + {Ts}} \right)} \\{{Hy}\left( {t + {Ts}} \right)} \\{H\;{z\left( {t + {Ts}} \right)}}\end{pmatrix} = {R_{\phi{(t)}}^{z}{R_{\theta{(t)}}^{y}\begin{pmatrix}{{Hx}^{\prime}\left( {t + {Ts}} \right)} \\{{Hy}^{\prime}\left( {t + {Ts}} \right)} \\{H\;{z^{\prime}\left( {t + {Ts}} \right)}}\end{pmatrix}}}} & \left( {{Expression}\mspace{14mu} 3} \right) \\{\begin{pmatrix}{{Hx}\left( {t + {Ts}} \right)} \\{{Hy}\left( {t + {Ts}} \right)} \\{H\;{z\left( {t + {Ts}} \right)}}\end{pmatrix} = {R_{\phi{(t)}}^{z}R_{\theta{(t)}}^{y}R_{\gamma{(t)}}^{x^{\prime}}R_{\delta{(t)}}^{z^{\prime}}{R_{\gamma{(t)}}^{x^{\prime}}\begin{pmatrix}{{Hx}^{\prime}\left( {t + {Ts}} \right)} \\{{Hy}^{\prime}\left( {t + {Ts}} \right)} \\{H\;{z^{\prime}\left( {t + {Ts}} \right)}}\end{pmatrix}}}} & \;\end{matrix}$where, R_(φ(t)) ^(z), R_(θ(t)) ^(y) in Expressions 3 show a rotationmatrix corresponding to the rotating manipulation of the angle φ(t)about the z-axis of FIG. 13 and the angle θ(t) about the y-axis.

The magnetic field generated from the outside can be calculated byrepeating these calculations.

In general, since the magnetic field of a coil is shown as follows.H=I·Nwhere, H: magnetic field, N: coefficient, I: currentAccordingly, the current I, that is, I=H/N is controlled.

When the coefficients of the three-axis Helmholtz coil are shown by Nx,Ny, Nz, respectively, currents Ix(t), Iy(t), Iz(t) that flow to thecoils are shown by Expression 4.

$\begin{matrix}{\begin{pmatrix}{{Ix}(t)} \\{{Iy}(t)} \\{{Iz}(t)}\end{pmatrix} = \begin{pmatrix}{{{Hx}(t)}/{Nx}} \\{{{Ny}(t)}/{Ny}} \\{H\;{{z(t)}/{Nz}}}\end{pmatrix}} & \left( {{Expression}\mspace{14mu} 4} \right)\end{matrix}$

As to the information of a capsule direction:

(1) when there is position direction detection means, θ(t), φ(t) areused based on a result of detection by the position detection means. NDIAurora®, and the like can be used as the position direction detectionmeans (sensor) at the time; and

(2) when no position is detected, θ(0), φ(0) (initial values) are input.

The direction of the capsule 3 thereafter is determined by Expression 5,and the direction is defined as the direction of the capsule 3.

$\begin{matrix}{\begin{pmatrix}{X\left( {t + {Ts}} \right)} \\{Y\left( {t + {Ts}} \right)} \\{Z\left( {t + {Ts}} \right)}\end{pmatrix} = {R_{\phi{(t)}}^{z}R_{\theta{(t)}}^{y}R_{\gamma{(t)}}^{x^{\prime}}R_{\delta{(t)}}^{z^{\prime}}{R_{- {\gamma{(t)}}}^{x^{\prime}}\begin{pmatrix}1 \\0 \\0\end{pmatrix}}}} & \left( {{Expression}\mspace{14mu} 5} \right)\end{matrix}$

Further, the capsule (medical apparatus) 3 shown in FIG. 3 has themagnet 16 disposed at a central portion of the capsule 3, the centralportion acting as a medical apparatus main body of the capsule 3. FIG.14 shows an internal layout view of the capsule 3.

The objective lens 13 attached to (an objective lens frame 51), theillumination elements 15, and the image pickup element 14 are disposedat the end of an observation window. Further, the signal processingcircuit 20 (it is built in the memory 21 in this case) and the wirelesscircuit 22 are disposed, and the magnet 16 is disposed behind thewireless circuit 22. The batteries 24 and a switch circuit 71 aredisposed on the opposite side of the observation window across themagnet 16. The respective units are wired through a flexible substrate56 as wiring means, thereby the capsule type medical apparatus 3 isarranged to realize the motion described above. With the above layout,the magnet 16 can be disposed at the central portion of the capsule typemedical apparatus 3. Further, in the above layout, the position of themagnet 16 is located near to the position of the center of gravity ofthe capsule type medical apparatus 3. With the above layout, therotation drive force and the like of the capsule type medical apparatus3 main body, which are generated by applying the magnetic field from theoutside, are generated in the vicinity of the center of gravity thereof.

Accordingly, the capsule type medical apparatus 3 can be stablycontrolled.

However, in the following case, better controllability may be obtainedby not disposing the magnet 16 in the vicinity of the center of thecapsule type medical apparatus.

FIG. 15 shows a capsule 3′ of a modification in which the location ofthe magnet 16 is changed with the location of the batteries 24 and theswitch circuit 71 in FIG. 14 so that the magnet 16 is disposed at theend opposite to the observation window side.

The above arrangement is advantageous when the capsule 3′ is guided intoa relatively large cavity of a colon and the like.

When a motion shown in FIG. 18(B) is executed, if the magnet 16 isdisposed in the vicinity of the capsule 3 as shown in FIG. 14, thecapsule 3 main body is vibrated as shown in FIGS. 6(A) and 6(B) by thevibration magnetic field applied thereto.

In contrast, when the magnet 16 is disposed as shown in FIG. 15, thecapsule 3 is vibrated by the vibration magnetic field applied theretosuch that the amplitude of the end of the capsule main body, which islocated on the observation window side, is increased as shown in FIG.17. With the above motion, the portion, where the inside wall of acavity is engaged with the capsule 3′, can be secured (increased) evenin a larger cavity.

Accordingly, the capsule 3′ has an effect that it can be guided eveninto the larger cavity.

Further, in FIG. 16, the magnet 16 is arranged to have a hollow astructure, inserted into the objective lens frame 51, and fixed therein.With the above structure, the magnet 16 can be disposed in the vicinityof the end of a capsule 3″ on the observation window side thereof.

How the capsule 3″ of FIG. 16 executes a different motion when it isguided (to make a direction change motion) will be explained incomparison with the capsule 3 of FIG. 3 and FIG. 14.

As shown in FIG. 18(A), the capsule 3 of FIG. 3 or FIG. 14 executes adirection change motion about the vicinity of the center of the capsule3 (the position of the magnet 16). Thus, when a cavity abruptly curves,there is a case that a turning-radius cannot be secured along the cavityand a guiding property is deteriorated.

In contrast, the capsule 3″ of FIG. 16 acts as described below.

That is, since the capsule 3″ changes its direction about the vicinityof the observation window as shown in FIG. 18(B), the turning-radius canbe easily secured.

Accordingly, the capsule 3″ has an effect that it can improve theguiding property.

According to the embodiment described above, even if a cavity, intowhich the capsule 3 and the like are desired to be inserted, is wider ornarrower than the outside diameter of the capsule 3 and the like orcurved, the capsule 3 and the like can smoothly pass therethrough,thereby the capsule 3 and the like can be guided to a target portionside in a short time.

Further, since the capsule 3 and the like can be moved in the cavity ata velocity higher than conventional arts, the capsule 3 and the like canbe guided to the target portion side in a short time.

Second Embodiment

Next, a second embodiment of the present invention will be explainedwith reference to FIG. 19. FIG. 19 shows a capsule 3B of the secondembodiment of the present invention. FIG. 19(A) shows an insidearrangement of the capsule 3B, and FIG. 19(B) shows a pager motor 57portion when it is observed from a rear end.

In the first embodiment, the magnet 16 is built in the capsule 3, andthe rotation magnetic field is applied to the capsule 3 from the outsideas well as the vibration magnetic field is applied thereto in adirection orthogonal to the rotation magnetic field. With thisoperation, couples are exerted on the capsule 3 so that it passivelyinclines its center axis C. In the present embodiment, however, aninclining force or a vibration force is exerted on the capsule 3B sothat it actively inclines its center axis C.

The capsule 3B shown in FIG. 19 includes a spiral projection 12 formedon the outer circumferential surface of a capsule-like exterior vessel11 likewise the capsule 3 of FIG. 3(A). Further, an observation window17 formed of a transparent material is disposed to the exterior vessel11 at an extreme end thereof.

A cylindrical objective lens frame 51 to which an objective lens 13 isattached is disposed in the inside of the capsule 3B in confrontationwith the observation window 17, an image pickup element substrate 52 towhich an image pickup element 14 is attached is disposed at the imagepickup position of the objective lens 13, and illumination elements 15are disposed around the objective lens frame 51.

A control substrate 53, which executes signal processing and control,and a communication substrate 54, which has functions of a wirelesscircuit 22 and the like, are disposed adjacent to the image pickupelement substrate 52, and an antenna 55 is connected to thecommunication substrate 54. Further, the illumination elements 15, theimage pickup element substrate 52, and the like are electricallyconnected through a flexible substrate 56.

A magnet 16 is disposed at a central position on the lengthwise centeraxis C of the capsule 3B such that the direction of the magnet 16orthogonal to the center axis C becomes the lengthwise direction thereofand fixed by a not shown adhesive or the like.

Further, batteries 24 are accommodated adjacent to the magnet 16 andconnected to the flexible substrate 56 through a not shown switch.Furthermore, the pager motor 57 is accommodated in an accommodatingportion in the vicinity of the rear end of the capsule 3B adjacent tothe batteries 24 and connected to a control substrate 53 and the likethrough the flexible substrate 56, the pager motor 57 being used todecenter or to vibrate so as to swivel the capsule 3B from the directionof the center axis C.

The pager motor 57 comprises, for example, an ultrasonic motor 58 and aweight 59 disposed to the ultrasonic motor 58.

As shown in FIG. 19(B), the ultrasonic motor 58 has a rotating shaft 58a to which the conical or fan-shaped weight 59 is attached. The weight59 is rotated together with the rotation of a rotor side of theultrasonic motor 58. With the above arrangement, a center of gravityposition change mechanism is formed whose position of the center ofgravity is changed depending on a position of the weight 59, thereby thecapsule 3B executes a swiveling motion (vibrates) as the weight 59rotates.

Further, the capsule 3B includes communication means to communicate witha processing device 6 outside of a body likewise the communication meansexplained in the first embodiment.

In the first embodiment, when the vibration switch 8 f of themanipulation/input device 8 is turned on, the control circuit 27 in theprocessing device 6 controls the magnetic field generation device 4 sothat it generates the vibration magnetic field. In the presentembodiment, however, a control circuit 27 transmits its indicationsignal to the capsule 3B side through a wireless circuit 25.

When the capsule 3B receives the indication signal and decodes thecommand, a capsule control circuit 23 (refer to FIG. 2, the controlsubstrate 53 in FIG. 19) operates the pager motor 57. Further, when avibration switch 8 f is turned off, the capsule 3B stops the operationof the pager motor 57. Note that a rotation magnetic field acts likewisethe first embodiment.

An operation of the embodiment arranged as described above will beexplained.

In the present embodiment, a manipulation for rotating the capsule 3B isthe same as that of the first embodiment. Then, when it is desired forthe capsule 3B to thrust through, for example, a curved cavity organmore smoothly, the vibration switch 8 f provided with amanipulation/input device 8 is depressed as shown in FIG. 2. Thus,vibration-ON-information is transmitted to the wireless circuit 25through the control circuit 27.

The vibration-ON-information is transmitted to the capsule 3B by awireless communication. On receiving the signal, the capsule controlcircuit 23 of the capsule 3B turns on the rotation of the pager motor57.

With this operation, the capsule 3B actively generates forces(pseudo-couples) for inclining or swinging it about its center axis C bypseudo-couples (that is, a force corresponding to one of forces forforming couples), thereby the capsule 3B can execute a vibrating motionor a swiveling motion. A method of obtaining a thrust by applying therotation magnetic field is the same as the first embodiment.

Note that when a signal for indicating the number of rotation of thepager motor 57 is set by a wireless communication, the frequency ofvibration can be changed.

According to the present embodiment, a simple manipulation can make thecapsule 3B to execute the vibrating motion or the swiveling motionwithout applying a vibration magnetic field from the outside.

Further, the capsule 3B may be thrust while being rotated by thecreeping motion of a cavity organ in a body through a spiral projection43B disposed around the capsule 3B in the state that no rotationmagnetic field is applied thereto. According to the present embodiment,the capsule 3B can be vibrated even in a small-scale system having nomagnetic field generation device 4 for generating a rotation magneticfield, thereby the capsule 3B can smoothly pass through a curvedportion.

Third Embodiment

Next, a third embodiment of the present invention will be explained withreference to FIGS. 20 to FIG. 21(B). FIG. 20 shows a capsule 3C of athird embodiment of the present invention, FIG. 21(A) shows anelectromagnetic solenoid device portion, and FIG. 21(B) shows anendoscope having a flexible tube disposed at one side end.

The capsule 3C shown in FIG. 20 has a built-in electromagnetic solenoiddevice 64. The electromagnetic solenoid device 64 electromagneticallymoves a weight 66 in place of the pager motor 57 in the capsule 3B ofFIG. 19(A).

As shown in FIG. 20, an electromagnetic solenoid device 64, whichcomprises an electromagnetic shield frame member 62 and a oscillator 63,is accommodated in an accommodating portion which is located in thevicinity of a rear end of the capsule 3C as well as adjacent tobatteries 24. The electromagnetic shield frame member 62 contains anelectromagnetic solenoid 61 and the like and covers them so that theyare not affected by the electromagnetic from the outside. Theelectromagnetic solenoid 61 can be magnetized in a direction orthogonalto a center axis C of the capsule 3C, and the oscillator 63 drives theelectromagnetic solenoid 61.

A vibration ON/OFF signal is sent to the capsule 3C by manipulating avibration switch 8 f of an external manipulation/input device 8 asexplained in FIG. 19. On receiving the ON/OFF signal, a capsule controlcircuit 23 of a control substrate 53 demodulates the ON/OFF signal andsends it to the oscillator 63, thereby the oscillator 63 is oscillated.The oscillator 63 generates a current for driving the electromagneticsolenoid 61 within the range of a frequency from a direct current toseveral tens of hertz.

Note that the drive condition of the oscillation frequency of theoscillator 63 may be preset. Otherwise, the oscillator 63 may bearranged such that a frequency signal can be input thereto in additionto an ON/OFF signal so that it can be controlled from the outside.

When the output signal of the oscillator 63 is supplied to theelectromagnetic solenoid 61 as a drive signal, the electromagneticsolenoid 61 is magnetized (generates a magnetic field).

Then, the weight 66, which is composed of, for example, a magnet movablyheld by a guide member 65, can be reciprocally moved in the axisdirection of the guide member 65 against the elastic force of a spring67 that urges an end of the guide member 65 (upper side in FIGS. 20 and21(A)) according to the magnetized direction of the electromagneticsolenoid 61. The capsule 3C is vibrated in the axis direction of theguide member 65 together with the reciprocating movement of the weight66.

FIG. 21(A) shows a more detailed structure of the electromagneticsolenoid device 64 portion in enlargement. The electromagnetic solenoid61 and the guide member 65, which is disposed in parallel with theelectromagnetic solenoid 61, are coupled with each other through pressermembers 68 a, 68 b, respectively and fixed thereby.

The weight 66, which has a hole through which the guide member 65passes, is attached to the guide member 65 so that it is free to move inthe axis direction of the guide member 65 and further urged upward by acoil-shaped spring 67 disposed under the weight 66.

Note that a stopper 69 is disposed to the presser member 68 b side sothat the movement of the weight 66 lower than a predetermined positionis regulated by the stopper 69.

Further, in the present embodiment, the presser member 68 a is composedof a non-magnetic member, and the presser member 68 b is composed of amagnetic member. Note that the electromagnetic solenoid 61 is controlledby a capsule control circuit in the capsule 3C.

Further, the motion of the electromagnetic solenoid 61 can be controlledby a manipulation/input device 8 of the processing device 6 outside of abody.

A signal input from the manipulation/input device 8 likewise in FIG. 19is transmitted to the capsule 3C through a wireless circuit 25 andtransmitted to the capsule control circuit 23. The capsule controlcircuit 23 controls the electromagnetic solenoid 61 based on the signal.

When a drive signal of an alternate current is supplied to theelectromagnetic solenoid 61, the magnetizing direction of theelectromagnetic solenoid 61 is changed, thereby the weight 66 composedof the magnet is reciprocatingly moved in an up and down direction.

Accordingly, the center of gravity of the capsule 3C is displaced,thereby a force, which rotates (or inclines) the capsule 3C about thelengthwise axis thereof, is exerted.

With the above operation, a passing-through property can be improvedwhen it is difficult to thrust the capsule 3C.

Note that the energization of the electromagnetic solenoid 61 may berepeatedly turned on and off in place of that it is driven alternatelyin response to the output from the oscillator 63. In this case, theweight 66 can be composed a magnetic member in place of forming it ofthe magnet. That is, an operation, which moves the weight 66 downwardwhen the electromagnetic solenoid 61 is turned on and moves (returns) itupward by the elastic force of the spring 67 when it is turned off, isrepeated.

That is, a force for causing the capsule 3C to swivel periodically canbe generated likewise the case that the capsule 3C is driven by theoutput from the oscillator 63. An effect in this case is almost the sameas the case of the pager motor 57.

Further, this embodiment has such a structure that the weight 66 ismoved by the electromagnetic solenoid 61. However, the embodiment may bearranged such that an ultrasonic linear motor is disposedperpendicularly to the insert axis direction of the capsule type medicalapparatus and the weight is attached to a drive unit of the ultrasoniclinear motor.

Further, the embodiments have been described entirely as to a capsularendoscope. However, any of the embodiments is by no means limited to thecapsular endoscope, and, as shown in, for example, FIG. 21(B), the sameeffect can be obtained even in an arrangement that a rotary slidingportion is disposed to one side end of the capsular endoscope and acatheter-like guide is provided therewith. Further, any of the vibrationmeans described above may be disposed in the endoscope so that anextreme end of the endoscope is vibrated.

Fourth Embodiment

FIGS. 22 to 30 relate to a fourth embodiment of the present invention,in which FIG. 22 is an overall configurational view showing an schematicarrangement of a capsule type medical apparatus guide system having afourth embodiment of the present invention;

FIG. 23 is a block diagram showing a more detailed arrangement of FIG.21; FIG. 24 is a schematic configurational view showing a schematicarrangement of a magnetic field generation device; FIG. 25 is a sideelevational view showing an external appearance of the capsule typemedical apparatus; FIG. 26 is a sectional view showing an internalarrangement of FIG. 25; FIG. 27 is a side elevational view of a watervessel in which a sample capsule, which is inserted into a silicon tube,is dipped to measure a thrust velocity by applying a rotation magneticfield thereto; FIG. 28 is a view showing a sample provided with a spiralprojection disposed at an end and used to measurement; FIG. 29 is a viewshowing a result of measurement of the thrust velocity; and FIG. 30 isan explanatory view of an action when a capsule is thrust through acurved cavity.

As shown in FIGS. 22, 23, and 24, the capsule type medical apparatusguide system (hereinafter, abbreviated as capsule guide system) 101includes a capsule-shaped capsule type medical apparatus (hereinafter,simply abbreviated as capsule) 103, a capsule controller (hereinafter,simply abbreviated as controller) 104, a magnetic field generationdevice (schematically shown in FIG. 22) 105, and an alternate currentpower source device 106. The capsule 103 is inserted into a body cavityof a patient 102 (shown in FIG. 1) and examines the inside of the bodycavity. The controller 104 is composed of a personal computer or thelike which is disposed outside of the patient 102, sends and receiveswireless waves to and from the capsule 103, controls the motion of thecapsule 103, and receives information transmitted from the capsule 103.The magnetic field generation device 105 controls the direction and thelike of a rotation magnetic field applied to the capsule 103 to therebyguide the capsule 103 in a direction where it is desired to be guided.The alternate current power source device 106 supplies an alternateelectric power to the magnetic field controller 5 so that it generates arotating magnetic field (electromagnetic field in more wide sense).

As shown in FIG. 23, the magnetic field generation device 105 iscomposed of, for example, three electromagnets 105 a, 105 b, 105 c andcontrols the alternate current power supplied from the alternate currentpower source device 106 so that a rotation magnetic field is generatedin three-axis directions. Note that, FIG. 24 schematically shows themagnetic field generation device 105 as a (hollow cube-shaped)three-axis Helmholtz coil formed in three-axis directions.

As shown in FIG. 23, the magnetic field generation device 105 forgenerating a rotation magnetic field is disposed around the patient 102,the alternate current power source device 106 is controlled from thecontroller 104 side, and the rotation magnetic field is applied to amagnet 108 (as a magnetic field response portion), to which a force isexerted in response to the magnetic field disposed in the capsule 103inserted into a tract of the body cavity of the patient 102, in adirection where the capsule 103 is thrust. With this operation, thecapsule 103 can be smoothly and effectively thrust (guided).

The direction of the rotation magnetic field, which is generated by themagnetic field generation device 105, can be controlled by manipulatinga manipulation/input device 8 connected to the magnetic field generationdevice 104.

As shown in FIG. 23, the controller 104 includes a personal computermain body 111, a keyboard 112, a monitor 113 as display means, anout-of-body antenna 114, and a manipulation/input device 109. Thepersonal computer main body 111 has a function for controlling thecapsule 103 and (the alternate current source 106) of the magnetic fieldgeneration device 105; the keyboard 112 is connected to the personalcomputer main body 111, and commands, data, and the like are inputtherethrough; the monitor 113 is connected to the personal computer mainbody 111 and displays an image and the like, the out-of-body antenna 114is connected to the personal computer main body 111, oscillates acontrol signal for controlling the capsule 103, and receives the signalfrom the capsule 103; and the manipulation/input device 109 is connectedto the personal computer main body 111, and the direction of therotation magnetic field, and the like are input therethrough.

As shown in FIG. 23, the controller 104 has a built-in CPU 115 whichcreates control signals for controlling the capsule 103 and the magneticfield generation device 105 based on inputs from the keyboard 112 andthe manipulation/input device 109 or on a control program stored in ahard disc 116 (refer to FIG. 23) in the personal computer main body 111.

The control signal for controlling the magnetic field generation device105 is transmitted from the personal computer main body 111 to thealternate current power source device 106 through a connection cable.The rotation magnetic field is generated based on the control signal.The rotation magnetic field generated by the magnetic field generationdevice 105 is magnetically exerted on the magnet 108 in the capsule 103and the capsule 103 is rotated thereby. As a result, a power forthrusting the capsule 103 is obtained from a thrust generationstructural portion described later.

In contrast, the control signal for controlling the capsule 103 ismodulated by a carrier wave having a predetermined frequency through anoscillation circuit in the personal computer main body 111 andoscillated from the out-of-body antenna 114 as a wireless wave.

Then, the capsule 103 receives the wireless wave as the control signalthrough an antenna 127 to be described later and outputs the controlsignal to respective constitution circuits and the like after it isdemodulated.

Further, the controller 104 receives information (data) signals such asa video signal and the like transmitted from the wireless antenna 127 ofthe capsule 103 through the out-of-body antenna 114 and displays them onthe monitor 113.

As shown in FIG. 23, accommodated in the capsule 103 are a signalprocessing circuit 124, a memory 125, a wireless circuit 126, theantenna 127, a capsule control circuit 128, and a battery 129, inaddition to an objective optical system 121 for imaging an opticalimage, an image pickup element 122 disposed at the image pickup positionof the objective optical system 121, illumination elements 123 disposedaround the objective optical system 121, and the magnet 108. The signalprocessing circuit 124 subjects the signal picked up by the image pickupelement 122 to signal processing; the memory 125 temporarily stores thedigital video signal created by the signal processing circuit 124; thewireless circuit 126 modulates the video signal read from the memory 125with a high frequency signal and converts it into a signal to bewireless transmitted, modulates the control signal transmitted from thecontroller 104, and so on; the antenna 127 transmits and receiveswireless waves to and from the out-of-body antenna 114; the capsulecontrol circuit 128 controls the capsule 103 such as the signalprocessing circuit 124 and the like, and the battery 129 supplies anoperation power to an electric system in the capsule 103 such as thesignal processing circuit 124 and the like.

Further, the personal computer main body 111, which constitutes thecontroller 104 for executing a wireless communication with the capsule103, includes a wireless circuit 131, a data processing circuit 132, theCPU 115 as control means, and the hard disc 116. The wireless circuit131 is connected to the out-of-body antenna 114 and executes a wirelesscommunication with the wireless circuit 126 (on the capsule 103 side);the data processing circuit 132 is connected to the wireless circuit 131and subjects the image data sent from the capsule 103 to data processingsuch as image display processing and the like; the CPU 115 controls thedata processing circuit 132, the alternate current power source device106, and the like; and the hard disc 116 stores programs, data and thelike. The CPU 115 is connected to the manipulation/input device 109 forsetting the direction of the rotation magnetic field and to the keyboard112 through which commands and data are input.

The monitor 113 is connected to the data processing circuit 132, and theimage, which is recorded by the image pickup element 122 and processedby the data processing circuit 132 through the wireless circuits 126 and131, and the like are displayed thereon. Further, since images arerecorded while the capsule 103 is being rotated, the data processingcircuit 132 executes processing for correcting the directions of theimages to be displayed on the monitor 113 to a predetermined directionso that an operator can observe the images easily.

FIG. 25 shows an outer shape of the capsule 103, and FIG. 26 shows aninside structure thereof.

As shown in FIGS. 25 and 26, the capsule 103 is airtightly covered with,for example, a hemispherical transparent extreme end cover 139 and acylindrical main body exterior member 140 to which the extreme end cover139 is connected airtightly. With this arrangement, an approximatelycylindrical capsule main body 141 whose inside is hermetically sealed isformed. Note that the rear end of the main body exterior member 140 isformed in an approximately hemispherical shape. As shown in FIG. 26, theoutside shape of the capsule main body 141 is formed symmetrically inrotation about the lengthwise center axis C of the capsule main body 141which is also a traveling direction of the capsule main body 141.

Further, a thrust generating spiral structure, which converts arotational motion into a thrust, is disposed on the outside surface ofthe rotation-symmetrical capsule main body 141. The spiral structure hasspiral projections 143 which spirally project from the cylindrical outercircumferential surface (base surface) 141 a of the capsule main body141 and come into contact with the inside wall of body cavity to therebyconvert the rotational motion into the thrust. Further, a spiral grooveis formed between the adjacent spiral projections 143 so that gases andfluids such as body fluids and the like in body cavity can communicatewith each other back and forth through the groove.

The components such as the objective lens 121, the illumination elements123 and the like described above are accommodated and disposed in thecapsule main body 141.

More specifically, the objective lens 121 is disposed at central portionof the capsule main body 141 inwardly of the extreme end cover 139thereof in the state that it is attached to a cylindrical lens frame144, an image pickup element substrate 145, on which the image pickupelement 122 is mounted, is disposed at an image pickup position of theobjective lens 121, and the plurality of illumination elements 123 aredisposed around the lens frame 144.

A control substrate 146, which executes signal processing and control,and a communication substrate 147, which has functions of the wirelesscircuit 126 and the like, are disposed adjacent to the image pickupelement substrate 145 as if they are laminated, and the antenna 127 isconnected to the communication substrate 147. Further the illuminationelements 123, the image pickup element substrate 145, and the like areelectrically connected through a flexible substrate 148.

Further, the magnet 108 is disposed approximately at central position ofthe length on the lengthwise center axis C of the capsule 103 such thatthe direction of the magnet 108 orthogonal to the center axis C becomesthe lengthwise direction thereof and fixed by a not shown adhesive orthe like.

Further, the battery 129 is accommodated adjacent to the magnet 108 andconnected to a flexible substrate 148 through a switch circuit 149.

Since the magnet 108 is disposed at the central position on the centeraxis C of the capsule main body 141 with the magnetizing directionthereof in a direction perpendicular to the center axis C, the rotationmagnetic field generated by the magnetic field generation device 105 isexerted on the magnet 108, and the capsule 103 is rotated by therotation force received by the magnet 108.

It should be noted that the magnet 108 used here is a permanent magnetsuch as a neodymium magnet, samarium cobalt magnet, ferrite magnet,chromium cobalt magnet, platinum magnet, AlNiCo magnet, and the like.

Since the rare earth magnets such as the neodymium magnet and thesamarium cobalt magnet have a strong magnetic force, they have a meritin that the size of the magnet built in the capsule can be reduced. Incontrast, the ferrite magnet has a merit in that it is less expensive.Further, the platinum magnet is excellent in corrosion resistance.

Further, in the present embodiment, as shown in FIG. 25, the extreme endsides of the spiral projections 143, which are formed on the outsidesurface of the capsule main body 141, extend up to a side of the capsule103 where it is formed in a hemispherical shape with its diameterreduced passing through the cylindrical outer circumferential surface ofthe capsule 103, and the end portions 143 a of the spiral projections143 are formed in a midstream of the diameter-reduced hemisphericalportion of the capsule 103, more specifically, at positions which arenot covered by the field angle of the objective lens 121. Further, therear ends 43 b of the spiral projections 143 extend to the vicinity ofthe boundary of the capsule 103 where it is formed in the hemisphericalshape with its diameter reduced. Note that, in the example shown in FIG.25, the spiral projections 143 are formed double (two lines) with one ofthe spiral projections 143 being disposed at an intermediate position ofthe other spiral projection 143.

In the embodiment arranged as described above, the spiral projections143 are disposed around the outer circumferential surface of the capsule103 as well as one end portions 143 a thereof are formed up to thepositions which reach the vicinity of the end of the diameter-reducedportion. That is, the spiral projections 143 have a feature in thatalthough they are formed around the cylindrical outer circumferentialsurface portion of the capsule main body 141, the one end portions 143 afurther extend up to, for example, the spherical portion whose diameteris made smaller than that of the cylinder and reach the boundaryposition which is not covered by the field angle (imaging area).

Since the spiral projections 143 are disposed up to the vicinity of theend of the capsule main body 141, a thrust function is enhanced asexplained below.

FIG. 27 shows a water vessel for measuring a thrust velocity using thecapsule main body 141 having the spiral projections 143 formed to thevicinity of the end of thereof. A sample (first sample) having (theoutside shape structure of the capsule 103 of the present embodiment) isdipped in the water vessel in the state that it is inserted into asilicon tube that simulates a cavity organ, water is poured into thewater vessel from an upper side (water depth is, for example, 20 cm) sothat a water pressure is exerted on the tube, and the thrust velocity ofthe sample is measured by moving it, for example, 2 cm by applying arotation magnetic field thereto from the outside.

Further, the thrust velocity of a comparative sample (second sample),which has the spiral projections of the first sample formed around onlya cylindrical surface portion, is measured under the same condition.FIG. 28 shows the outside shape of the first sample. Note that thesecond sample has the spiral projections formed only on the cylindricalsurface thereof in the first sample shown in FIG.

FIGS. 29(A) and 29(B) show results of measurement obtained using thesesamples. The results of measurement shown in FIGS. 29(A) and 29(B) areobtained by plotting the average values of measurements executed 10times. The frequency of the rotation magnetic field is set to 0.5 Hz, 1Hz, and 5 Hz.

Further, it is assumed that the thrust velocity is proportional to thefrequency, and lines, which are linearly approximated by a least squaresmethod, are drawn.

FIGS. 29(A) and 29(B) show the results of the same experiment bychanging a scale of a frequency and a velocity. Note that the data shownby circles is obtained by the sample having no spiral projections formedat the extreme end (simply abbreviated as without extreme end in FIG.29(A)), and the data shown by triangles is obtained by the sample havingthe spiral projections formed also at the extreme end. Further, FIG.29(A) shows the case of a frequency and a velocity up to 5 Hz, and FIG.29(B) shows the result of measurement up to 1 Hz in enlargement.

It can be said from the data of measurement that the thrust velocity ofthe sample, which has the spiral projections formed up to the endportion, is about 1.4 times larger than that of the sample without thespiral projections in the vicinity of the end portion. It can be saidthat this exhibits that the spiral projections at the end portioncontribute to the thrust force.

Further, another characteristic action achieved by the capsule 103 ofthe present embodiment will be explained with reference to FIGS. 30(A)and 30(B).

When it is intended to thrust a capsule in a curved direction of, forexample, a curved cavity organ 155 as shown in FIGS. 30(A) and 30(B), itis difficult to thrust a capsule 103′ having the spiral projectionsformed only around a cylindrical portion as shown in FIG. 30(B) even ifit is rotated. This is because that the spiral projections are unlike tobe engaged with the concavo-convex portions such as folds on the insidewall of the cavity organ, and thus it is difficult to smoothly thrustthe capsule 103′.

In the present embodiment, however, since the spiral projections 143 areformed up to the vicinity of the end portion whose diameter is furtherreduced as shown in FIG. 30(A), the capsule 103 can be more smoothlyrotationally thrust even in the above state by engaging the spiralprojections 143, which are formed up to the vicinity of thediameter-reduced portion, with the concavo-convex portions of the insidewall of the cavity organ.

As described above, this embodiment is characterized in that the thrustforce can be enhanced and the capsule 103 can reach a target portion ina short time because the capsule 103 is rotationally driven by disposingthe spiral structure, more specifically, the spiral projections 143 alsoin the vicinity of the diameter-reduced end portion as well as thecapsule 103 can be more smoothly thrust along a curved tract by thespiral projections 143 formed also in the vicinity of the end portion.

Next, an operation of the capsule guide system 101 provided with thespiral projections 143 will be explained below.

As shown in FIG. 22, when it is necessary to observe the inside of thebody cavity of, for example, a duodena 151 side, an intestinum tenueside, or the like of the patient 102, the operator causes the patient102 to swallow the capsule 103 from a mouth 152.

Note that, at this time, the operator previously turns on the switchcircuit 149 of the capsule 103 just before the patient 102 swallows itso that the power of the battery 129 is supplied to the illuminationelements 123 and the like. Simultaneously with the above operation, theoperator starts (turns on) the magnetic field generation device 105 andmagnetically controls the capsule 103 so that it is caused to easilyreach a target portion side in the body cavity by the rotation magneticfield generated by the magnetic field generation device 105.

As described above, in the capsule 103, when the magnet 108 acts on therotation magnetic field generated by the magnetic field generationdevice 105, the capsule main body 141 is rotated by the action receivedby the magnet 108. When the capsule main body 141 comes into contactwith the inside wall of the body cavity, a friction force between themembrana mucosa of the inside wall of the body cavity and the spiralprojections 143 is converted into a large thrust force, thereby thecapsule 103 is moved forward and backward. Further, the travelingdirection (direction) of the capsule 103 is changed while the capsulemain body 141 is being rotated so that the rotation plane of the magnet108 agrees with the rotation plane of the rotation magnetic field as therotation magnetic field rotates.

At this time, in the capsule 103, capsule main body 141 can thrusttoward the target portion side in the tract of the body cavity.

Since the capsule 103 is swallowed by the patient 102, it passes throughthe esophagus 153 from the oral cavity 152 and reaches the inside of astomach 154.

When it is necessary to observe the inside of the stomach 154, theoperator depresses a key corresponding to an observation start commandfrom, for example, the keyboard 112 of the controller 104. Thus, acontrol signal input from the key is radiated as a wireless wave throughthe out-of-body antenna 114 of the controller 104 and transmitted to thecapsule 103 side.

The capsule 103 detects a motion start signal from the signal receivedthrough the antenna 127, thereby the illumination elements 123, theimage pickup element 122, the signal processing circuit 124, and thelike are placed in a drive state.

The illumination elements 123 emit illumination light in the directionof the field of view of the objective lens 121, and an optical image inthe range of the illuminated field of view is formed on the image pickupelement 122 located at the image pickup position of the objective lens121 and photoelectrically converted. A resultant optical image issubjected to A/D conversion by the signal processing circuit 124 andconverted into a digital signal, which is stored in the memory 125 afterit is subjected to compression processing. Thereafter, the compresseddigital signal is modulated by the wireless circuit 126 and radiatedfrom the antenna 127 as a wireless wave.

The wireless wave is received by the out-of-body antenna 114 of thecontroller 104, demodulated by the wireless circuit 131 in the personalcomputer main body 111, further converted into a digital video signal bythe data processing circuit 132 through A/D conversion, and stored inthe memory of the data processing circuit 132 or in the hard disc 116.Then, the digital video signal is read out at a predetermined velocity,and the optical image recorded by the image pickup element 122 isdisplayed on the monitor 113 in color.

The operator can observe the inside of the stomach 154 of the patient102 through the observation of the image. The operator can easilycontrol an external magnetic force to be exerted using the manipulationmeans such as the joy stick and the like of the manipulation/inputdevice 109 while observing the image so that the operator can observethe entire region of the stomach 154.

Further, on the completion of observation of the inside of the stomach154, the operator can magnetically guide and move the capsule 103 fromthe stomach 154 to the duodena 151 side by controlling the direction ofthe rotation magnetic field generated by the magnetic field generationdevice 105 with respect to the capsule 103. Then, the operation cansmoothly thrust the capsule 103 also in the duodena 151 by controllingthe direction of the rotation magnetic field so that the capsule 103travels in the direction of the body cavity of the duodena 151.

Further, when the capsule 103 is caused to travel in a curved tract suchas the intestinum tenue, it can be caused to smoothly travel even in thecurved tract. This is because that the spiral projections 143 are formedup to the vicinity of the spherical end portion of the capsule main body141 as explained in FIG. 30(A).

As described above, according to this embodiment, since the capsule 103can be smoothly thrust, an examination time can be shortened as well asa burden, fatigue and the like of the operator and the patient can bereduced.

Further, since the capsule 103 of the present embodiment does not moveuselessly, a magnetic field guide efficiency can be enhanced, which isalso effective in that the magnet 108 in the capsule main body 141 andthe electromagnets 105 a, 105 b, 105 c disposed outside of the body canbe reduced in size.

Fifth Embodiment

Next, a fifth embodiment of the present invention will be explained withreference to FIG. 31. FIG. 31 shows a capsule 103B of the fifthembodiment of the present invention. In the capsule 103B, spiralprojections extends further backward and formed up to the vicinity ofthe end portion of a capsule main body 141, in contrast to the capsule103 of the fourth embodiment in which the rear ends 143 b of the spiralprojections 143 are located at positions in front of the rear end of thecapsule main body 141.

The other arrangement of the capsule 103B is the same as that of thecapsule 103 of the fourth embodiment.

As an operation and advantage of the present embodiment, even when thecapsule 103B is moved backward, it can be moved effectively as well aswhen capsule 103B is moved to a curved rear side, it can be also movedsmoothly.

FIG. 32 shows a capsule 103C of a first modification. The outsidediameter of the capsule 103C smoothly changes from an extreme end to arear end like a leaf roll shape, in contrast that the outside shape ofthe capsule 103B shown in FIG. 31 is formed in a hemispherical shape.

Since the outside diameter of the capsule 103C smoothly changes from theextreme end to the rear end, it has an excellent insert property.

FIG. 33 shows a capsule 103D of a second modification. In the capsule103D shown in FIG. 33, the outside shape of the capsule main body 141thereof is formed to have taper portions 161 with their diametersreduced by forming both the ends of a central cylindrical portion of thecapsule main body 141 in a taper shape (conical shape). Then, theextreme end and rear end sides of the capsule main body 141 are formedin a flat shape as if they are cut away.

A good insert property can be obtained because the extreme end coverside and the rear end side are formed in the diameter-reduced tapershape. Further, since the extreme end cover side and the rear end sideare formed in the cut-away shape, the capsule 103D can be reduced insize.

FIG. 34 shows a capsule 103E of a third modification. The capsule 103Eshown in FIG. 34 is arranged by rounding the extreme end and the rearend of the capsule 103D of FIG. 33 in an approximately spherical shapein place of the flat shape.

That is, in the capsule 103E, the outside shape of a capsule main body141 is formed to have taper portions 161 with their diameters reduced byforming both the ends of a central cylindrical portion of the capsulemain body 141 in a taper shape (conical shape). Then, the extreme endside and rear end side ends of the capsule 103E are formed in anapproximately spherical shape.

A good insert property can be obtained in the modification because theextreme end cover side and the rear end side are formed in thediameter-reduced taper shape.

FIG. 35 shows a capsule 103F of a fourth modification. In the capsule103F shown in FIG. 35, a pitch b, at which spiral projections 143 areformed in a spiral shape on the outside surface of a capsule main body141 in, for example, central portion thereof having a largest outsidediameter, is set same as pitches a and c, at which the spiralprojections 143 are formed in the portions of the capsule main body 141,which are located on the extreme end side and the rear end side of thecentral portion and have a smaller outside diameter, that is a=b=c.

Since the spiral projections 143 are formed on the outside surface ofthe capsule 103F at the constant pitch, when the capsule 103F rotatesand is pushed out by being engaged with the concavo-convex portions ofthe inside wall surface of cavity organ, the capsule 103F can beeffectively thrust because it is contemplated that the concavo-convexportions of the inside wall surface of the cavity organ remainapproximately invariant.

Further, the pitches are set constant, when the capsule main body 141 ismade by machining, it can be simply machined by setting an amount offeed of a lathe constant with respect to the rpm thereof, thereby thecapsule main body 141 can be made at low cost. Further, since the amountof feed per rotation of the capsule 103F in a small diameter portion isthe same as that in a large diameter portion, a thrust can beeffectively generated in the capsule 103F in its entirety.

Further, a fifth modification may be arranged as described below.

The respective capsules 103B and the like described above are arrangedas a type without cable having neither a line nor a tube attached to arear portion. However, they may be arranged as capsule type medicalapparatuses of a type with a cable which have a flexible tube freelyrotatably attached to the rear portion thereof (on the side opposite tothe extreme end cover 139).

In this case, the capsule type medical apparatuses can be moreeffectively thrust or moved backward by combining the thrust executed bythe spiral structure with the pulling and pushing executed by the tube.

Sixth Embodiment

Next, a sixth embodiment of the present invention will be explained withreference to FIGS. 36(A) and 36(B). FIG. 36(A) shows a capsule 103G ofthe embodiment, and FIG. 36(B) shows an example of an image obtained bythe capsule 103G.

The capsule 103G shown in FIG. 36(A) is arranged such that a hollowstructure is provided with the spiral projections 143 of, for example,the capsule 103 of FIG. 31 by forming hollow portions 162 in the spiralprojections 143 along the lengthwise direction thereof, the hollowportions 162 having open ends 162 a which open in the end portions 143 aon the extreme end side of the spiral projections 143. In addition tothe above, the end portions 143 a are extended to positions which arelocated inwardly of a view angle so that the end portions 143 a can beobserved (on an obtained image) as shown in FIG. 36(B).

Further, in the capsule 103G, a hollow portion is formed in a capsulemain body 141, an accommodating portion 164, in which a medicine can bestored, is formed in the hollow portion, and a micro pump 166, whichdrives for feeding (or discharging) and suctioning, is interposedbetween the accommodating portion 164 and a tube 165 which connects theaccommodating portion 164 to the hollow portions 162 of the spiralprojections 143. With this arrangement, the medicine 163 stored in theaccommodating portion 164 is discharged to the open ends 162 a at theextreme end through the hollow portions 162 of the spiral projections143 so that the patient and the like can be subjected to a therapeutictreatment by the medicine given to an affected area and the like.

Further, when the micro pump 166 is rotated inversely, it can suctioninside-body substances such as a body fluid and the like from the openends 162 a and accommodate them in the accommodating portion 164. Forexample, first, the medicine 163 stored in the accommodating portion 164is discharged to the affected area and the like from the open ends 162a. Thereafter, the inside-body substances such as the body fluid and thelike are accommodated in the accommodating portion 164 by rotating themicro pump 166 inversely, and the capsule 103G is discharged from theinside of the body. Then, the inside-body substances are taken out fromthe capsule 103G and can be examined in detail.

According to this embodiment, since the spiral projections 143 as thespiral structure are also used to discharge the medicine 163, the spiralstructure can be used to thrust the capsule 103G and to discharge themedicine 163, thereby the capsule 103G, which is small in size and has afunction for picking up an image of the inside of a body cavity and afunction for discharging the medicine for the treatment, can berealized.

Further, there can be realized the capsule 103G having a function forcollecting inside-body-cavity substances such as a body fluid in a bodycavity and the like.

Further, since the end portions 143 a of the spiral projections 143 areextended to the positions inwardly of the view angle, a thrust can bemore enhanced as well as the medicine 163 can be discharged from theopen ends 162 a disposed to the end portions 143 a, and when theinside-body substances are suctioned, a suctioning operation can beconfirmed on an obtained image.

Note that the capsule 103G of FIG. 36 may be used only to discharge themedicine 163 and only to suction and collect the inside-body substances.

Various sensors such as pressure sensor, pH sensor, temperature sensor,blood sensor, and the like may be disposed at the open ends 162 a of thehollow portions of the spiral projections 143, and the wirings of thesensors may be disposed along the hollow portions 162. A different typeof sensors may be disposed to each of the plurality of spiralprojections 143 or the same type of sensors may be disposed to it. Thisarrangement is more convenient because the portions and positionsmeasured by the sensors can be confirmed on an image simultaneously withthe discharge of the medicine 163 or the collection of the body fluid.

FIG. 37 shows a capsule 103H of a modification. The capsule 103H isarranged such that the accommodating portion 164 is not disposed in thecapsule 103 of FIG. 36(A), and a micro pump 166 disposed in the capsule103H is connected to the hollow portions 162 of two spiral projections143 formed double.

When the micro pump 166 is rotated, for example, clockwise, it executesa suctioning operation from an upper side to a lower side in FIG. 37,thereby the body fluid and the like can be suctioned into the hollowportion 162 of a spiral projection 143 whose cross section is shown inFIG. 37 and stored therein.

Further, when the micro pump 166 is rotated counterclockwise, the bodyfluid and the like can be suctioned into the hollow portion 162 of theother spiral projection 143 and stored therein.

That is, in this modification, it is possible to suction the inside-bodysubstances such as the body fluid and the like and substances to beexamined from, for example, different portions into the hollow portions162 of the spiral projections 143 disposed double and collect themtherein. This modification has substantially the same advantage as thatof the capsule 103H of FIG. 36.

Note that the magnetic field response portion, which is built in thecapsule 103 and the like and acts as the magnet 108, may be formed of aferromagnetic body such as iron and the like or of a magnetic body inplace of the magnet 108. Further, an electric field may be applied inplace of the magnetic field, and a charged body or a dielectric may bebuilt in the capsule 103 and the like.

Note that embodiments and the like which are arranged by partlycombining the respective embodiments described above also belong to thepresent invention.

In this invention, it is apparent that working modes different in a widerange can be formed on the basis of this invention without departingfrom the spirit and scope of the invention. This invention is notrestricted by any specific embodiment except being limited by theappended claims.

1. A capsule endoscope for executing a medical action in a cavity organof a body to be examined, the capsule endoscope comprising: anuntethered main body further comprising: a rotation symmetrical memberhaving a symmetrical axis in a traveling direction, the symmetrical axisfurther defining a front end and a rear end of the rotation symmetricalmember; and a front diameter-reduced portion arranged to the front endof the rotation symmetrical member and a rear diameter-reduced portionarranged to the rear end of the rotation symmetrical member, the frontand rear diameter-reduced portions each having a diameter which reducestoward the symmetrical axis of the rotation symmetrical member; anelectromagnetic field response portion disposed in the untethered mainbody and acted by the rotation of an electromagnetic field applied fromthe outside of the body to be examined; a spiral structure, disposed onat least a portion of an external surface of the rotation symmetricalmember of the untethered main body and at least a portion of an externalsurface of the front diameter-reduced portion of the untethered mainbody, for converting the rotating motion generated by theelectromagnetic field response portion into a thrust; and an imagepickup system, provided inside the front diameter-reduced portion of theuntethered main body, for picking up an image, wherein an end of thespiral structure is disposed on an external surface of the frontdiameter-reduced portion of the untethered main body so as to reach thevicinity of a boundary of an imaging area of the image pickup system. 2.The capsule endoscope according to claim 1, wherein the pitch of thespiral structure is constant regardless of a shape of the main body. 3.The capsule endoscope according to claim 1, wherein the electromagneticfield response portion comprises a magnetic substance or a magnet. 4.The capsule endoscope according to claim 1, wherein the electromagneticfield response portion comprises a dielectric substance.
 5. The capsuleendoscope according to claim 1, wherein the spiral structure of themedical apparatus comprises a plurality of spirals.
 6. The capsuleendoscope according to claim 1, wherein the diameter-reduced portion isformed in a taper shape.
 7. The capsule endoscope according to claim 1,wherein the spiral structure has a hollow portion.
 8. The capsuleendoscope according to claim 7, further comprising a storage portion forstoring at least a medicine, the medicine stored in the storage portion,and a discharge portion for discharging the medicine, and the medicinedischarged by the discharge portion passing through the spiral structurehaving a hollow structure is discharged from an end of the spiralstructure.
 9. The capsule endoscope according to claim 7, wherein atleast a substance-in-body suctioning portion and a storage portion forstoring a suctioned substance are disposed in the main body, and an endof the spiral structure having the hollow portion is used as asuctioning port for a substance-in-body.
 10. The capsule endoscopeaccording to claim 1, further comprising at least one image pickupsystem including an image pickup element, and a lens system forcondensing the light captured from the outside to the image pickupelement, wherein at least one of the diameter-reduced portions is formedby a light transmitting member for capturing the light to the lenssystem, and wherein the end of the spiral structure is disposed on anexternal surface of the light transmitting member so as to reach thevicinity of a boundary of an imaging area of the image pickup element.11. The capsule endoscope according to claim 1, further comprising aflexible tube attached to the main body.
 12. A capsule endoscope forexecuting a medical action in a cavity organ of a body to be examined,the capsule endoscope comprising: an untethered main body furthercomprising: an approximately cylindrical portion having a first end anda second end, and a first diameter-reduced portion disposed on the firstend of the approximately cylindrical portion and a seconddiameter-reduced portion disposed on the second end of the approximatelycylindrical portion, the first diameter-reduced portion and the seconddiameter-reduced portion each having a diameter which reduces towards asymmetrical axis of the approximately cylindrical portion; a magnetdisposed in the untethered main body and magnetically acted by arotation magnetic field applied from the outside of the body to beexamined; a spiral structure disposed on at least a portion of anexternal surface of the approximately cylindrical portion of theuntethered main body and at least a portion of an external surface ofthe first diameter-reduced portion for converting the rotating motiongenerated by the magnet into a thrust; and an image pickup systemprovided inside the first diameter-reduced portion of the untetheredmain body, for picking up an image of a subject, wherein one end of thespiral structure is disposed on an external surface of the firstdiameter-reduced portion so as to reach the vicinity of a boundary of animaging area of the image pickup system.
 13. The capsule endoscopeaccording to claim 12, wherein the pitch of the spiral structure isconstant regardless of a shape of the main body.
 14. The capsuleendoscope according to claim 12, wherein the spiral structure issmoothly connected in a connecting portion between the approximatelycylindrical portion and the diameter-reduced portion of the medicalapparatus.
 15. The capsule endoscope according to claim 12, wherein thespiral structure of the medical apparatus comprises a plurality ofspirals.
 16. The capsule endoscope according to claim 12, wherein thediameter-reduced portion is formed in a taper shape.
 17. The capsuleendoscope according to claim 12, wherein the spiral structure has ahollow portion.
 18. The capsule endoscope according to claim 17, furthercomprising a storage portion for storing at least a medicine, themedicine stored in the storage portion, and a discharge portion fordischarging the medicine, and the medicine discharged by the dischargeportion passing through the spiral structure having a hollow structureis discharged from an end of the spiral structure.
 19. The capsuleendoscope according to claim 17, wherein at least a substance-in-bodysuctioning portion and a storage portion for storing a suctionedsubstance are disposed in the main body, and an end of the spiralstructure having the hollow portion is used as a suctioning port for asubstance-in-body.
 20. The capsule endoscope according to claim 12,further comprising at least one image pickup system including an imagepickup element, and a lens system for condensing the light captured fromthe outside to the image pickup element, wherein at least one of thediameter-reduced portions is formed by a light transmitting member forcapturing the light to the lens system, and wherein the end of thespiral structure is disposed on an external surface of the lighttransmitting member so as to reach the vicinity of a boundary of animaging area of the image pickup element.
 21. The capsule endoscopeaccording to claim 12, further comprises a flexible tube attached to themain body.
 22. A capsule endoscope guide system comprising: a capsuleendoscope comprising: an untethered main body comprising: a rotationsymmetrical member having a symmetrical axis in a traveling direction,the symmetrical axis further defining a front end and a rear end of therotation symmetrical member, and a front diameter-reduced portionarranged to the front end of the rotation symmetrical member and a reardiameter-reduced portion arranged to the rear end of the rotationsymmetrical member, the front and rear diameter-reduced portions eachhaving a diameter which reduces toward the symmetrical axis of therotation symmetrical member, an electromagnetic field response portiondisposed in the untethered main body and acted by the rotation of anelectromagnetic field applied from the outside of the body to beexamined, a spiral structure, disposed on at least a portion of anexternal surface of the rotation symmetrical member of the untetheredmain body and at least a portion of an external surface of the frontdiameter-reduced portion of the untethered main body, for converting arotating motion generated by the electromagnetic field response portioninto a thrust, and an image pickup system, provided inside the frontdiameter-reduced portion of the untethered main body, for picking up animage, wherein an end of the spiral structure is disposed on an externalsurface of the front diameter-reduced portion of the untethered mainbody so as to reach the vicinity of a boundary of an imaging area of theimage pickup system; electromagnetic field generation means forgenerating the electromagnetic field acting on the electromagnetic fieldresponse portion disposed in the untethered main body; andelectromagnetic field control means for controlling the direction of theelectromagnetic field generated by the electromagnetic field generationmeans, wherein the electromagnetic field generation means generates theelectromagnetic field in three-axis directions and rotates the medicalapparatus in a cavity organ.
 23. A capsule endoscope guide systemcomprising: a capsule endoscope comprising: an untethered main bodyfurther comprising: an approximately cylindrical portion having a firstend and a second end, and a first diameter-reduced portion disposed onthe first end of the approximately cylindrical portion and a seconddiameter-reduced portion disposed on the second end of the approximatelycylindrical portion, the first diameter-reduced portion and the seconddiameter-reduced portion each having a diameter which reduces towards asymmetrical axis of the approximately cylindrical portion, a magnetdisposed in the untethered main body and magnetically acted by arotation magnetic field applied from the outside of a body to beexamined, a spiral structure disposed on at least a portion of anexternal surface of the approximately cylindrical portion of theuntethered main body and at least a portion of an external surface ofthe first diameter-reduced portion for converting the rotating motiongenerated by the magnet into a thrust, and an image pickup systemprovided inside the first diameter-reduced portion of the untetheredmain body, for picking up an image of a subject, wherein one end of thespiral structure is disposed on an external surface of the firstdiameter-reduced portion so as to reach the vicinity of a boundary of animgaing area of the image pickup system; electromagnetic fieldgeneration means for generating the rotation electromagnetic fieldacting on the magnet disposed in the untethered main body of the capsuleendoscope; and electromagnetic field control means for controlling thedirection of the electromagnetic field generated by the electromagneticfield generation means, wherein the electromagnetic field generationmeans generates the electromagnetic field in three-axis directions.